There is almost no point in leveling up and caring for your soldiers, because if they die, you can hire another one of the same level. Or even higher level.
Replayability suffers greatly because of this. Replaying from the start will never feel like a different playthrough, because you will feel every mission as a scripted part of the story, and not an effort to accomplish a goal.
The tactics part, though, is awesome. Outrageous gore and some exciting moments makes this a very fun game.