I'm currently decked in 4* demo along with a plethora of 4* bombs, however I don't fell like I'm helping much most of the time. My damage seems to be rather bland, and the freeze or vortex bombs don't do much as the creatures often get knocked out. Anyone have any tips for bomber or I should I just grab a gun and sword like everybody else?
Bombs excel at 5*, where they gain much more effectiveness. Most bombs gain a larger radius, shorter charge time, and other effects.
Vortexes gain a larger suction, and a stronger hold on the enemies. If you aren't, I suggest changing to the electron line. Require pvp farming, but the weapon is well worth it. The shock infliction at the end of the bomb prevents flinging enemies, allowing you and your team to wail on them some more.
Rss is a very good bomb, but lacks the punch without damage bonus, either from trinkets or armour. Main source of elemental damage, and usable on just about every monster type due to split damage.
Dark briar barrage, dbb, is the piercing bomb of many pure bomber's choice. Large radius, pure piercing, it destroys wolver dens and devilish drudgery.
Have you obtained bombs in the other haze lines, namely fire and shock? Those are extremely helpful in terms of dps, and the shock provides a decent amount of control.