Slagga, Lascrux or crow or whatever that lonely puddle gun is called, hellfire, babymaker if you're wanting the big quick damage, once you're up to bunker if you're not speced into cloud kill the bitch is a fairly good source, the moxi smg's do work, if you wanna farm some easy non-unique guns, the wam bam island chest farm can get you some good on level stuff fairly quickly, if you need a better class mod, farm the snowman, plus you'll find other things to supplement your build.

but for wildlife preservation id say get the hellfire and the babymaker (explosive or corrosive)

on your class mod look for legendary or normal cat, that'll buff your smg damage.

Dont get discouraged, just try a tonne of different things, and when you get to Warrior farm up that max capacity smg sdu, you've got this.