I really don't like the UI, very little is explained when I hover over stuff (look for tooltips with "?" in bottom right, they get larger if you keep the mouse on them). Sometimes the UI just gives me wrong info; says I'll kill an enemy guaranteed in an attack and then it fails. And that monstrosity that is city building, both normal and "advanced" - rarely do I say this but the UI for that should just be thrown out. Such a shame with a beautiful city 3d overview.
I loathe having to "explore" provinces just to uncover places I can visit. It works thematically, but just makes for very boring gameplay over time. I like the idea on paper, it just seems so overused. Dom3 handled exploration of magical sites a lot better.
I liked the combat. The game seems to have fewer active/passive abilities for units, but they are much more traditional than say LH or Might and magic Heroes 6 (this is a good thing). I don't really get if flanking is a thing, or if I can surround enemies. As for complexity I can't really say, haven't played enough. The AI certainly didn't throw me any surprises, every fight played out more or less as I expected.
I found the durability system for items tiresome and not fun at all. Although the game does appear to have randomized items (I think?), ie suffixes, prefixes. Which is great.
I'm going to keep playing but so far the game doesn't stand out as very good to me, nothing has given me any "wow" sensation and I don't have the "one more turn" feeling either.
Edit: How's modding like?