Controlling a party of 6 in the typical infinity engine combat system is what the Icewind Dale (but also the BG games) were designed for.
For me those combat systems are rather relaxing, you can pause any time (or even use autopause) to give commands as slowly as you want, compare it to classic rts games like Command&Conquer or Warcraft where you both had to command many units and also build at the same time without being able to pause for giving orders.

If you're lazy you simply give a ranged weapon to everyone, assign the fighter ranged attack script to everyone (the bard script works very well for the party bard too), enable AI, maybe place some summoned meatshields in front of your party and watch your characters shoot at the enemies arriving attacking your summons, only giving special orders in the toughest battles.


IWD2 can be soloed with any class. A duo will work too but I'm not sure if it's easier than soloing.
Unlike the other games IWD2 uses dynamic XP calculation, as higher level adventurer you get less or even no XP for killing low level monsters, so your duo or solo characters won't get 3 or 6 times the XP members in a full party of 6 would get, they'll only be a few levels higher and it will be difficult.

I suspect that a solo bard would be easier to play than a duo consisting of bard and fighter since the bard has self-protection spells (mirror image) and will level faster and get access to higher level spells since he won't have to share the quest XP (combat XP will be almost nonexistent anyway).
If you play a bard don't choose half-elf, humans get an extra feat and an additional skill point per level even with 3 int.

If you play a party of 2 consider installing the "Always Get Some XP Per Kill" component from the IWD2 Ease-of-Use by Westley Weimer so you do get some combat XP and level a little faster, even with it you won't reach the level cap.

Fighter is the weakest class for soloing or small parties, barbarians get damage reduction and greater rage at higher levels, paladins special abilities and a few spells. Cleric and sorcerer are the most powerful classes.
Fighters get only bonus feats and after the best feats are taken the remaining ones get less and less useful while other classes start to shine at higher levels.

Ok. I think I may have a solution. Im gonna try Icewind Dale 1 and see how a 2 person party of the same works. I got past 2 chapters in the first game as well but was playing a whole party so I wasn't enjoying it.

I'll try that setup in that game and then see how it fares in the 2nd game later. Thanks for your help, unless you have any more advice for that game. You have been very helpful ;)

IWD1 uses totally different rules than IWD2 so a setup which works in IWD1 often doesn't work in IWD2 and the other way around.
With small parties IWD is easier to play than IWD2, you could simply combine fighter/mage/thief multiclass with a ranger/cleric multiclass and have everything (fighting, priest spells, mage spells, thievery) covered for example.