I'll have to agree about the movement of units on walls, but you have to admit.... Its been improved a lot from RTW. It still is somewhat lacking, however.

Don't get me wrong, i think this game is awesome, one f the best i've ever played, but there are a few things that, if changed, could make for a much more enjoyable playing experience.
In my opinion, the main factor is the almost complete disregard of armor. Is it just me, or is armor worn to deflect enemy blows? The one hit KO's by peasants at fully armored knights seems a bit off to me. Maybe this was aceptable in RTW, where all the units were a lot less armored.
I think MTW was pretty good in this respect, where units would swing repeatedly at other units, a lot of their blows glancing off their opponents armour. And even without armour, i think it would take more than one shot to drop an opponent.
Maybe i'm wrong, but i'm just simply annoyed at seeing units standing about, taking their time, carefully deliberating before attacking, and when they attack, their attacks seem to be perfectly aimed as to kill their oponent (usually) in one shot.