Running through game currently as a Kraxis Archsummoner. Took Path of the Mage. Running on the same world game settings as AlLanMandragoran (nice WoT ref, incidentally), using your custom map.
Thoughts so far... actually not been having too much trouble. That Shadow Warg is pretty beastly, and if it dies (which happens every so often, though I did lvl that first one to 6 before it finally bit it in a fairly epic battle) I just simply summon another one. Between that, a Assailant Path of the Warrior Hero (who keeps dying and getting injured - is there a way to make a game item outside of the quest restoration potion that can get rid of injuries? or is there already one?), a Path of the Warrior Defender, and two lvl 9 mercs I've gotten from scrolls, I can generally steamroll through all the early game stuff - I haven't had to actually make a unit yet.
Not sure if you want this to be a viable strategy, but I did something a bit amusing - once I unlocked the Nightswatch, I built a city right next to an Obsidian Golem camp, and then immediately Rushed a Nightswatch. Golems left, I raid the ruins, and get that nice Legendary Greatsword as loot. Granted, can't use yet, but it worked - Golems are just puttering over on the other side of the mountains (which, now that I think of, I might want to seal that pass off... just in case).
Problem: ran into an AI problem if you auto-fight (not auto-resolve, auto-fight) during a tactical battle - I took the Path of the Cleric trait, which gives you... I think it's called Restoration? Really nice heal spell, which for some reason is listed as a skill? for relatively cheap. If I auto-fight, he keeps using it whenever it is up to heal himself... even if he's at full health.
Other than that, definitely enjoying the game so far. I find that if possible (and you're strong enough), it really helps to beeline toward killing those spawn camps, trying to avoid as many fights on the way in as possible - if you kill the source, then you can mop up the spawns afterward.
I'll probably come up with some more things as I go - will try to keep you updated.