The injury system is in a good place right now.
I even have a couple of guys who suffered permanent injuries with me, still remember the fight – my first against Orcwarriors – in wich my best ranged brother got ‘Traumatized’ and think of it everytime I see the injury.
It adds so much character and gritty realism to the game, please keep it.
(Edit: I also don’t think they’re too expensive to treat either, you normally get more from every fight/contract the brother got injured in.)