To be honest, the boltshot was only bad because it was a starting weapon. It was the equivalent of spawning with the mauler in halo 3. I think they can keep it, given that it is not a starting weapon and rather a power weapon (which it is). As for the light rifle, I think it was an okay gun, but after the update became useless. They need to work on balance alot better in Halo 5 ( which I'm sure they will do so). I'm erudite with regards to competitive halo play, and I believe that the weapons can work so long as they're balanced.