I think it would be okay to do this (took me about 4k coins to get both of the guns, but I know that some people can roll these boxes in 1-2 tries, so whatever goes, as you said, some are lucky, some are not). Still, it probably won't make much of a difference. All that is needed right now imo is some rebalances (remove all this L/S/H stuff, it's not needed), removal of the grenade launcher (or at least don't make it stun), and bring back the normal hitbox