My father and I have been playing this mod religiously for the past month, and these were the the issues that stood out in our minds:
The biggest is the Dwarves. They really don't seem to have anything going for them at all, esspecially because they are so udderly dependent on iron. The toughness of their foot units (+1 or +2 hp) isn't really special when orcs and chaos get units like their Ogres, beastemen, and trolls that don't require a resource to build. The gyrocopter, saltpeter units, and airship are decent, but they're just too little too late. Perhaps, just to give them a unique edge, Dwarf foot units could be allowed to pass through mountains?
AI wise Chaos and the Dwarves both play very passively early game and half the time seem to stiffle completely and barely expand. Looking at my games with them as foes, I noticed they weren't hooked up to horses or iron and didn't really have any available. Both of those civs don't really have a designated offensive unit, especially early game, without horses and/or iron. It might help the AI function a bit better for races that don't get an archer offense unit with balistics to play better if they had an alternative, like the Marauder and the Dwarf 6/4/1 (the name escapes me at the moment) not requiring iron.
The Dolgan's Horse Archer is rather sad for being their golden age unit. Requiring 10 less shields to build compared to other Horse archers isn't really enough to set it apart for them. Perhaps they could be allowed to have their horse archer sooner then military training at Riding or Balistics? They seem like an early conquest civ, and having played them, they really struggle later game if the other civs had time to develope.
And maybe someone has said it before, but if the Slann Mage Priest can bombard offensively, why are all the other 'caster' units defensive fire only? Even with a bombard range of 1 I'd be more inclined to use them. As it is right now, I'll make an entire army of Slann mage-priests as the Lizardmen, and won't even wast time building units like the Damsel, Sorcerer, Shaman, etc as the other races, except maybe the Khemri's Liche because that far into the game it's (sadly) the most powerful unit they get until dragons.
Or would it be possible to allow casters to carry a spell? Flag them to transport tactical missiles, flag the spells tactical missiles, and set their transport to 1. I'm pretty sure that will work. The downside is they couldn't board ships anymore, so that seems like a 6 in 1 half dozen in the other trade off to me.
Casters could be allowed to use wizard towers and spelltowers to teleport to make up for not being shippable? The trouble with the spelltower is it can't be built in hostile territory. So by the time you could build one to stage spells and use them offensively, the front line will have probably moved back out of spell reach except maybe lightning bolts. Even trying to do that by using recently captured slaves wasn't even close to being useful when a city could be taken or built.
Of course, this is just the thoughts of 2 people, and I know our play styles are probably radically different from many other people's. So... I hope these suggestions aren't taken badly. They are just lil things we believed could bring even more fun to a great mod. (Sorry if any of this has been brought up before, it takes a long time to catch up on the history of this mod's developement.)