Your firing pin ideas have occurred to me, I just find the whole thing unsatisfying. They don't do anything, you know? Like Nova Bomb could instead have just been some small single use hand fired rocket launcher, that would be boring. Space Magic is exciting and fun. Some weirdly, almost impossibly placed firing pin is just dumb. It doesn't make me go "ooh future", like Hard Light or Vex, it just makes me squint at it confusedly.