Ok so I think I have finally "got" the commander. I did the brigands start like in Dedmihai's stream and it works pretty well. I tried it on a expert map first and then in my campaign at master.
On the expert map it was a bit hairy because there were no plains, not much money. On the master campaign it was a bit difficult at the start, because the brigands had a morale penalty due to my karma being pretty high. How could you start with a commander being "The Pure"? Maybe spearmen?
Anyway, you basically just level up the commander while you replace brigands, and then kill stuff with more brigands till you have enough cash for better units like barbarians, crossbowmen or swordsmen.
Now at turn 70 my strategist has crossbowmen with over 10 range attack and they are really tough in defense as well. The horse archers are pretty cool,too.
Also I am having less reversions because weak units aren't so vulnerable thanks to the commanders boni. I feel that this hero is stronger than a mage or scout at this point. I just don't see how he would improve much from now on.

Overall it is great fun, give it a try, it's just awesome to have alot of strong ranged units take out everything that comes close.

Yes. Spearmen, Healers, Archers, Soldiers. Once you have the Soldiers, you can stop using the Spearmen if you have the money and Steel.
(I don't remember well the names)

That would be so awesome, but where to get Hydras! But I can see that a mage com/mage would be pretty useful, the strategist didnt really do much.
But I really enjoyed the +4 and later +6 range attack for the units. The whole game felt more "strategic" because you have so many units. And most of them are expendable because the newly recruited crossbowmen and horse archers are strong enough thanks to the strategist bonus.

This game just keeps on giving.

Yeah, the strategist is really powerfull : Many units with high firepower that can mow down most enemy armies, a very good mobility (3 moves/turn on any terrain if you take the right skills) that allow him to strike anywhere on your territory, and a decent ranged attack for himself. Quite costly due to the maintainance costs of his trrops (which makes him harder to use on swampshards), but I love him.
I try to play all the classes for variety, but I use him as primary hero in the campaign shards I can't afford to lose (home defense and special campaign quests). :)

Its your game but I can't agree. The Commander makes a good (sometimes best) 2nd hero on large or crowded shards because once you get him up and running things are fine.

The trouble is he takes so long to get moving and sucks money like a crack head sucks {censured}... this is normaly money that you don't have or is needed to build up a city. The archer on the other hand can fight right out of the box and can explore/ battle things in the home province which quickly builds your units & is much, much faster than a Commander start.

Once you have your buildings made and are ready to start pushing against someone elses border is when having a Commander comes into his own but IME taking him from turn 1 will just slow you down.

Yes he does suck up alot of gold, in my last few games I ran deficits till the end! But I noticed the opposite on the slowness, I have won games now faster than ever before. If you start with brigands you don't have to wait or explore, I also successfully did it with Spearmen now,but thats harder. Although barbarian provinces were strangely much easier, probably because the 4 thrown spears hit them pretty hard. One usually dies like that, the second gets fatigue spells and dies easily, the third and the shaman are doable with 4 spearmen and the commander.
On a medium, or maybe large, map I took out the first master on turn 70, the next on 90 and won at 120, the enemy masters heroes were like half his level, this was on master and I think they were overlords. You can take on crazy stuff once he gets to level 10.

I'm only playing the campaign with beginner difficulty so take my comments with a pinch of salt.

At first I normally started with the archer and some pikemen and a healer.

After some consideration I switched to the commander and a load of barbarians.
He sucks as a unit, even on beginner difficulty but he has one more unit slot.
But If you hire barbarians as soon as they go beserk their morale won't matter anymore, and four barbarians are pretty powerful against most neutrals on ring one.
Combined with Astral Energy and Web spell you can controll the battlefield easily.

Now, have you considered that he gets his first tier 2 unit on what? Level 3?

Of course you haven't had the time building tier 2 units, but with a tad of luck you ran into harpies or the most brütal thing every: a fairy tree, right?
You start dominating the battlefield with dryads and faires while other heroes rely on items, shops and their spells and can't even recruit one damn harpy. Dryads have magic attacks, so ghosts don't matter anymore and stop hampering your progress.

Gargoyles from a Magic shop?
Yes, flying tier 2 units which just cost gems instead of gold...

Now when does the commander get to tier 3? Level *uhm* 5 or mabye 7.

You know you can recruit minotaurs from a labyrinth if you are lucky...
Finally taking chances at the labyrinth becomes interesting.
With one minotaur on turn 15 (or 20) or something you can wreck all oposition from Ring one, ring two, on easier difficulties probably even with ring three with auto on.
Of course there is a lot of luck involved, but finding the right monsters and items for the other heroes is luck based as well.
If you don't want to overuse the labyrinth because you don't want to press your luck you can use your minotaurs and harpies and dryads to assult troll lairs, recruiting them instead...

Who needs citadel upgrades if you can use the provinces and sites around you?

How much money can you save, simply by not building tier 2 or tier 3 buildings and rely on scouting for a fairy tree and a troll cave.

By the time tier IV units are interesting your trolls and minotaurs are so powerful (Round attack, forced march, regeneration, dryads even get healing auras) that you can laugh off paladins, cyclopses and vampires and those pesky stone guardian shop guards.

If you don't mind low morale have you ever tried using fairies with Trolls?
Haste spell, Healing + Troll regeneration is mighty powerful combination.

Additionally, considering that trolls even get a siege bonus you can waste the enemies citadel before he has a change to relocate his strong hero back for a defense. Especially in combination with the logisics skill.
You simply become a mighty horde overrunning any enemy defenses while economy becomes less of a hassle.

Just one tier 2 recruiment station (Fairy tree, harpy's nest or magic shop) and your commander becomes the most powerful hero. Try comparing that with finding a powerful sword/armor/spell or bow on ring one provinces.

Some monks just handed me Elven Blades when my warrior was still conquering ring one - probably my favorite gift from that particular karma-specific event so far :)

But anyway, the Warrior is still my starting + ending hero of choice, though it takes a few turns of exploring before I risk him in any battles (need Library, Wizardry School, Forge at least.)