Converse with fellow players
Rod vs Talis is just preference on playstyle. strength and weakness is minor difference. its pretty much short vs long on normal hits.
i not sure about Class skills, tho.
go see Quest Clerk, check expendition, Ark mission, sub mission for weapon you seek. Each quest have own 2 weapon rare drop per difficulty.
one of them may have what you seek.
old guide for gunner's sub-class, may help you to decide.
Server is back up, and keep this in mind, we will have Weekly maintenance like today. so expecting the same thing next week.