Can't comment on the number of injuries - not been around enough. But the associated kit cost for injuries is too high imo. You can fully fix mental health problems with 2 kits. This cost problem I'd guess is due to the association between Training and Injuries - if it was too cheap to fix injuries then Power Training would be even easier.

I'd have thought if injuries in training affected the availability for training (say by a CD prohibiting further training that day) then maybe the number of kits per day of injury could come down. Bit of realism lost but hardly a biggie.