Yeah, the grenade thing is a tad iffy. I think it's supposed to count for flubbing a throw and having it bounce, but it really comes across as your recruits having suffered brain damage sometimes. Instructions inclear, shoved portable nuke into shoe. Like I think the odds of a grenade backfiring in Silent Storm was even higher, but it was usually your fault, because you aimed for a window, it missed the window, hit a pipe, and rolled back down. Or those moments when it flew, hit a guy, and rolled back. Either way, XD's fix to this was just to give them a really nice accuracy bonus. Somehow they still couldn't aim past smoke worth a crap, but not sure how they pulled that off. Just would be nice to have backfires be rare, rather than the norm for sure.
I'd imagine the balance will be nicer, they are working on a crap load of other stuff for now, nothing's going to be balanced.