Campaign map.
The approach to city building and everything else concerning cities is completely changed. For the worse.
Restrictive and boring sums it up quite accurately. Town garrisons are now automatic and you have no ability to choose free upkeep units yourself.
Population affects the number of buildings you can have in your town. Maximum of 6 in your provincial capital and 3 or 4 in other towns. And one or two of those building slots will always be taken either by settlement type or food production.
Population gets mad and start rioting if you have smithy, farms or walls in town. Taxes have only a minor role in overall happiness. Seriously?
You can't lead any armies without generals.
So what happened to me is that I've conquered the whole Britannia (except Ireland), and now I have 5 settlements and I'm stuck with a total of three armies.
Now I must launch an invasion on Ireland and leave all of my provinces completely undefended.
The whole system is idiotic to say at least. It's horribly restrictive and forces you to play the way somebody intended you to play. There's no fun in that.
My advice: skip the game.
Hopefully they won't make the same mistakes with Warhammer TW.