One of my favorite things about collecting exotics is that many of them shine in some specific contexts. Vex is powerful when Specialist is in play. MIDA and Bad Juju are great in the Abyss. Red Death heals you in the Crota encounter. Super Good Advice crushes Oracles. Etc. I think adding Arc or Void damage (Solar is already well covered) to some of the lesser used exotic primaries would make them more interesting and help them see more action. You balanced Gally to make people switch things up more, which I think is great, but I think adding burns would also help.