Yeah, the great bow is definitely too much. Longbows at 13 damage are considered quite powerful in dominions, and crossbows at 10 ap every 2 rounds even more so against armored targets. 15 ap every round for just one more resource than a longbow is not just good, it's
ridiculously good. 10 ap is enough to consistently damage 20 prot, but not much higher. 15 ap is enough to consistently damage 30. Against more normal units with protection values ranging from 8-16, each shot fired from these great bows has a VERY good chance of killing your average human. Compare this to a crossbow, a crossbow will do the same amount of damage on average to a guy with 6 protection (militia) as a great bow will to a guy with 16(tough heavy infantry). They are really, really powerful in dominions with those stats.
Hopefully I haven't come across as being too harsh, I'm just trying to show you the math behind why everyone is saying they're too powerful
. Personally, I would replace the horsebow with longbows and the great bows with the hinnom bows as others have suggested. This will enable you to use them with flaming arrows and make the great bows much less unreasonable. I think they would be better at +1 damage over longbows than +2, but I think it's a reasonable compromise.
The Tengri pretender - Expensive little chassis, but still ridiculously overpowered
. At current price, you can take it awake while still having pretty good scales and decent dominion (or balanced scales and dominion NINE). Couple this with high awe, higher than 100% lightning resist (why?), 100% poison resist, immortality, ethereality, 0 enc trample, bunches of AN attacks, and an insanely high storm power value... if you can get this things #onebattlespells working, it will truly be an undefeatable monster. I am not kidding. And on top of that it has good buffing+mobility magic paths built in. He needs serious work to be fair. As an aside, for some reason in the pretender screen he is listed as having s3 and a3, but when I look at his magic paths to increase them, he only has them at 1. Not sure what's going on there.
Ulgen - Well, he's certainly no Tengri, so he's much more reasonable. Largely he seems a bit of a niche pretender... sort of like a sphinx on steroids, that can create mages (if GoRed, which is still cheaper and much less research than normal) I'm a bit concerned about his domsummon ability, and the amount of misc slots he has seems a bit much (same with the last guy too). It would be pretty easy to stack this guy with boosters and cast several great globals and spells, and you can get the magic to do so while taking him awake without sacrificing your scales.
Gazar Eej - Much more reasonable chassis. Possibly still better than its cost, and yet again the extremely high level of awe, but otherwise I don't see anything glaringly wrong with it. As a suggestion, consider bumping its cost to 100 points and lowering the awe to +1 or +2.
Genghis - Too many misc slots. Three maybe, but 4 just seems like too much. The level of fear could also drop a bit. Perhaps to +2? Other than that he is not too bad. I might actually lower his price though. Not all the way down to 0, but say somewhere around 20. Simultaneously, consider bumping his new path cost to 60-80.
Erlik - Why does he #onebattlespell undead mastery? This is an insanely good ability, way too good to be a #onebattlespell. Why not darkness? That seems reasonably thematic and not so overpowering. Either way he I think he is too cheap. He should probably be at least 150 points, and also, have fewer misc slots
It seems also that he has a lot of magic paths. A pretender with three seperate magic paths probably should not be so skilled in a particular one. Especially not if he has such a high dominion score. I notice all of your pretenders have very high dominion scores. You might want to consider toning some of them down. For example, in vanilla there are only something like 2 pretenders with a dominion of 4, and those are the fountains, which have fairly low utility as far as pretenders go. Whereas all of yours are powerful mages, SCs, army enhancers, etc
Consider bumping most of them down to 1 or 2 dominion, leaving Genghis with high dominion to represent his authority and ability to command.
I'm not going to talk much about the troops. Cavalry look more or less okay except for the ones with light lances, who suffer from a lack of dexterity and have lower attack values than intended. The basic infantry are slightly good for troops that are supposed to be a bit meh, but are probably fine. Qayan vessels having spy and assassinate is weird, but since they can't use those abilities it doesn't matter that much. The archers are just too good, even at 35 gold per. Even if they were cap only and 50 gold per archer, they would be too good :P Why do the javelin launchers have 0 encumbrance and all those resists?
One last thing... death worms. Their stats aren't too ridiculous, but their price is too low, and their attacks are way too good. They shouldn't be more than aoe1, and no, the worms really don't need fear :P
That was way longer than I'd intended... again, I hope I don't come off to harshly, everything I said above is just my personal opinion and entirely capable of being wrong!