So, here's my idea for a small party of 2:

- Mook-Ninja (class-changed from Psionic at level 4); development: DEX/SPD > STR/SEN
- Rawulf-Valkyrie (class-changed from Samurai at level 8); development: STR/VIT/SPD > DEX/PIE


In detail:

1. Male MOOK Ninja
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- Dual Wielding (possibly some kickass sword and a Nunchaka) for Melee
- Throwing (also dual wielding, ideally Boomerang Shuriken / something else) for Ranged
- Locks & Traps

=> Why Mook? Mook seems to be a strange choice for a Ninja due to its rather low basic DEX and SPD (and yeah, the pitiful PIE hurts as well). My main reasoning was that the Mook has excellent resistances in the most important realms (Water vs. Paralysis, Mental vs. Insanity, Divine vs. some Death spells), which I figure is even more important in small parties due to the lack of potential healers of any given condition.

=> So why no Faerie? I usually love faeries. Well, apart from the excellent resistances and the AC bonus, people usually take Faerie Ninjas for the famed Cane of Corpus. The big problem is that this weapon is cursed, which means you cannot make use of the Ninja's throwing skill anymore. Which is a big deal. So you have to decide early: Cane or Throwing? The thing is, if you skip the Cane, you can train your ninja in other weapons that are almost as powerful (swords) AND still use your Throwing skill. Now, you might still use a Faerie without the Cane of Corpus, but some equipment restrictions and the 1/3 penalty to carrying capacity (which is a serious penalty in small parties) finally made me decide against this race.

Build:
1. Creation as a Psionic with the following Stats:
STR 50, INT 55, PIE 30, VIT 61, DEX 52, SPD 52, SEN 60 (50 bonus points).
As you see, I've put the bonus points into PIE(5), VIT(11), DEX(17) and SPD(17). DEX and SPD are obvious, not only because 55 each is a Ninja requirement, but also since I want to focus on them for development anyway. Vitality I DON'T want to focus on at all, but it helps to start with a good basis. Hit points during level-ups only increase with VIT for the upcoming levels, so it's a good thing to do this in the beginning. I expect to get hit more often with a small party, so more hit points are probably a good thing to have (even though VIT doesn't help developing any skill). And PIETY, though I do want to ignore it basically, I just had pity with the tiny 25 figure and made it 30 at least. Ideally this should be even higher (spell points, stamina, magic realms development), but there are more imporant things to work on.
2. The goal is the (especially for the first half of the game) quite important Insanity spell, which I can get by level 3. I only have to get my Psionics to 15 for that.
3. Change to a Ninja at level 4. Pump some points into Locks & Traps, then train this skill on some early chests. Continue to develop DEX and SPD up to 100 each, then move to STR and SEN.


2. Female RAWULF Valkyrie
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- Dual wielding Sword/Mace (Diamond Eyes as secondary weapon)
- Polearm as extended range weapon

Here the deal is to start as some Wizardry using character to get Missile Shield and Enchanted Blade, which are very important spells only open to the Wizardry school. One way to do this would be to create a Mage and do the same thing as for the Psionic (important to keep a spell pick in order to get both MS and EB by level 3) and the change to Valkyrie. The only problem with this idea is that a party of 1 Psionic and 1 Mage wouldn't survive very long, at least it would be EXTREMELY hard to get to level 4.
So the alternative was to create a Samurai and change to Valkyrie by level 8. Which is what I did. Your class change is delayed, but you get some points in Cricital Strike instead, which cannot hurt even for a Valkyrie.

Build:
1. Creation as Samurai with the following Stats (-5 Bonus points):
STR 50, INT 55, PIE 55, VIT 50, DEX 55, SPD 55, SEN 50 => Change to Valkyrie at level 8.
2. Development: First pump STR and VIT, until VIT reaches >60 (reasoning: see Ninja), then turn to STR and SPD. Why SPD again, and not DEX? Well, I won't have access to the Haste spell, and Initiative is very important, especially since this character will be casting Bless, Soul Shield and other supportive spells, which should take effect before the opponents can act. More attacks/swings is a nice bonus. And a DEX of 55 is a reasonable basis to The reason for STR is obvious: This character will carry a lot of gear and wants to do a lot of damage (+ Powerstrike skill). Once STR and SPD are maxed, pump DEX and PIE.


Any comments, ideas, etc. are appreciated (especially by people who have experience with small parties).

Looks like a solid plan. I don't have any experience with small party's thou and much prefer a large party all my own!

During > 100 runs through the game incl available mods and Reforged 1.2 testruns,
i had a ninja at ~80% in the party or as the solo character, always play on expert
(also provides fastest skill improvement from regular combat),
and dont like or use fairies, especially because of the prime example for an OP item aka cane of corpus.

The Val/Sam in your example has no stealth,
so she will get all melee and most ranged attacks with stealth going up, which you can not prevent.
In case i recommend 1 level in related class early, to power train stealth to at least 90+with both.

For easier/safer(or whatever) IM solo runs in tough mods i change from Nin to Bis at some point
and let him learn all spells up to 4th level to get max sppts, all buffs and x-ray as one of the most important spells.
I powertrain all magic schools and realms to at least 90,
also in a cheap way by endlessly casting spells(mana stones!) with square symbol at unseen enemies.

I prefer humans because they get the highest number of attribute points on character build,
so i get highest base on what can not be trained in game, which i can complete with attribute bonus items.
Note that members of imported parties get up to 10 bonus attribute points, but their attribute values are determined by the game,
it tends to balanced characters, i.e. fresh made PCs may get power skills earlier.
Resistance bonuses from mag screen&realms shields should be sufficient for vanilla,
racial bonuses in addition to that may be useful if a mod requires even higher resistances,
but such mods should contain something to compensate that, else i would not call them balanced. And fix it.

My ninjas usually also pump dex and speed to max attacks+swings/turn, followed by sen&str respectively &int if combined with bishop.
I concentrate on throwing and martial arts and/or polearms, especially if a mod contains much foes with extended reach.
From my experience, a close weapon near max skill needs 10%+ kill chance to outperform MA near max, only the light sword will do it for ninjas as a not cursed item.
To max ranged, i go to umpani shooting range as Bis with doubleshot sling and thousands of bullet stones. Rest when the HPs of the 3 dummies go near zero ...
To max crits/unfamiliar weapons with Nin cast Guardian Angel on the victims, else they will be instakilled too fast.
Sometimes i inspect traps repeatedly, so i dont need to put any lvlup points in locks&traps.

Note that effects of Int bonus items are always useful for training, Ankh of Death for combat and Red Silk Gown to reduce CC crits.

Thanks for the insight.

Do you have any knowledge about how the Martial Arts damage is calculated?

No, i only know that dmg and also attack value of MA rises with lvl and probably skills in CC&MA,
go to inventory page, click the shield&sword button and compare values from same PC at different lvls to get an idea.
To get a precise formula in reasonable time you could use a savegame or hex editor to adjust a PC
and add items with increasing bouses to all possibly related skills and attributes.
Or, preferably, extract the source code:D

Sounds like a good game plan, as ur two commandos gets training in most of there stats with little bit of magic. But I do think it will be hard in late game when fighting constantly an army of enemies in wizardry 8. But hey, that is why we have armies for parties in these games ;) .

One thing about Martial Arts, in my experience, is that you absolutely need the Monk's 25% skill bonus for it to be viable; having a Ninja use it doesn't work that well.

I advise against powertraining Stealth when soloing, as it makes battles long (because enemies keep defending, making your attacks less effective) and boring (because enemies don't attack you, so there's no danger). In fact, I prefer to avoid classes with the Stealth skill entirely.

Well doing a low party system is not really about fun, but the ability to beat a game withs odds completely stack against you. And how hard a wizardry game be at times, abusing the stealth system would actually help with most of his playthrough with few times reloading the game after defeat.

Ok, I've tried this out and ran into some problems, which are mainly cause by the rapid levelling up of those two guys. Both are around level 8 now, which is quite high for this time in the game, but couldn'r really be helped. Lower Monastery was fine, but in the Upper Monastery I run into hoards of Rabid Rats repeatedly, and in the Assistant Room near the exit there are even 3 Metallic Slimes, which are just too much for my little party. I don't even want to know how hard Arnika Road will be.

Probably I would have needed to do some more training in Stealth and Weapon skills earlier (Stealth maybe, as proposed here, for both characters), but right now it seems quite tough to continue. Maybe I could try to buy loads of bombs from Burz and see what can be done. Maybe I just have to start over.

Any tips on how to manage this?

Try to get the surprise whenever possible, e.g. move to next cover and initiate combat,
if you havent X-Ray yet you can check whether the game allows to cast a spell with square symbol,
note that possible targets also could be friendlies.
Or select to move in comabt and take a look whats behind the corner, cornifere or whatever you used as cover.
Dont rush the enemies, step back into cover and end combat.
Enemies will be alerted if they saw you once and try to close up even if you are unseen now,
so If you want to avoid combat you have to run away for a decent time or initiate combat in cover once again to end it immediately,
both will end their "search and destroy" behaviour.
If you decide to fight them, initiate combat and throw your bombs from cover respectively move only so far that you can see one enemiy or as much as you can kill in one turn.
If things go bad run away and use potions to charge again asap and finish the rest.
To restore the stamina loss from all the running, initiate combat repeatedly.

It's been my experience that using a very small party tends to work better if you import them from Wizardry 7. While that starts you out at level 5 so you hit a lot more nasty enemies on the Arnika Road, your skills also tend to be higher and better balanced to start and there are a few items you can bring that can really really help in the early stages.

Metallic slimes, for instance, become extremely easy if you have a Stun Rod. One they're paralyzed or k.o'd you can kill them at your leisure, and the Stun Rod is an excellent weapon as well. The Diamond Ring, if you also played Wizardry 6, can be very useful as well by giving one of your characters a good AC/regen item to start, and the Ring ALWAYS imports, too. (Also consider the Spear of Death from Wiz 6, it's got good damage and range, and it's one-handed so you can use it with a shield.) If you're using a Ninja, starting with a nunchaka or sai can make your life a lot easier.

These sorts of parties can be done, and they can be a lot of fun as well. I played a Lord and Ranger pair all the way through 6, 7, and 8 and it was incredible.