I honestly love this game, despite the many things that are much worse than Warband. For one, the graphics are a tad worse (not that i care anyway) and personally i find some of the armour in this game to be absolutely hideous, understanding that this is a different culture of course. but lets get to a list, shall we?
-seems to run smoother than Warband
-You can hire and customize mercenaries of your choice
-more indepth caravan system
-fighting feels more challenging, in a good way
-for sieges, there are more options to choose from before commencing the assualt. also you can blow holes in the wall
-this is more of a personal thing, but, different cultures and factions, like Sweden and Poland (although i do love Warband's factions)
-you can have a not-so-fancy-gentlemen's-duel with random drunk tavern guests, (this is where the thrust only swords can come in handy)
-Enemy firearms can be OP at low levels
-some weapons are specifically thrust only
-rather boring early game
-the map is rather bland compared to Warband
-the explosives have a limit, if you have 5 bombs and use 5 bombs in one battle, you have to buy another 5 bombs because the other 5 bombs get removed from your inventory
-Modding is more limited, unlike Warband's Module system (however, there is a WFAS enhanced mod that makes the game awesome)
That is about all i can think of right now. If you do get this game, look into the WFAS enhanced mod i mentioned above to make your experience a bit better.