The gremlins are really hard to get the hang of, but easily one of my favorite crews. The gun line was my least favorite way to go, until the Ophelia box was released, I like the crew you built, it would work great, and i would love to try it myself.
You were also asking for another crew to counteract the gremlins, hmmm. I would go with either Colette or Ramos, they have powers that are totally different, Ramos in particular is easy to pick up, but hard to master, so he is a good master to learn with, and should be a fun fight.