unfortunately your weapon balancing ideas are just your personal thought, and we dont have the tools like Bungie does to take such a staggering sizeable sample of what's being overused to kill people. If bungie senses an imbalance, i'm sure they'll fix it. The fuel rod cannon, though: I'm pretty sure the reason it doesn't make it's appearance as a default weapon is because it consumes resources; more so than the other weapons, and in active environments could cause unstability in framerates. It's the same with the firebombs.