That's something i like in Pendor, the mercenary troops that you can hire are actually quite good and sometime better than the ones you're training at your current level of trainer (and your own level), making then hiring mercs something very good.
Talking about Pendor, i wonder if they will improve the challenge balance in M&B2.
Warband is challenging in the early game, then it fall into medium/easy in the midgame , and sadly is too easy in the late/endgame (full knight charge can simply win the whole game at that point, even in siege without horses knights can kill whole guarison, tested that myself), making then the mid/endgame much less interesting.
An area of the gameplay i would like to see improved too.
Pendor went the other way, early game is completely ridiculous (you damaging the enemy for 0 damage and getting one hit killed by everything cease to be fun quickly, but fortunately it's where you learn to hire mercs to get something decent and slowly progress in your own strength and equipment to match the troops) , then midgame is challenging as enemy lords have as powerfull troops as you, and end/lategame can still provide some challenge (the neutral armies hunt to conclude the game).
And Pendor knights while still extremely powerfull are not the unbeatable unit they are in Warband, even high end foot infantry can be a match to those horse tanks, and without mentionning noldor archers that can bring a powerfull knight charge in open terrain into a disaster for them.