In a group it's firstmost about teamwork. (if you've ever read X-men you should know this.)
When working as a team you have to make some adjustments to how You want to play, this goes for everyone.
So please wait until tank has herded the mobs into a group and troller has immobilised them before firing off your [insert nuke flavor of the day here]. And if possible, try to target the mobs on the outside of the big fight, so that they don't just run up and squish the support. Oh, and also, try to stand in range of the healers aura.
and sometimes you just got to jam a fistfull of insps and run into a group and nuke them, only to find you didn't quite kill them... that is part of being a blaster. 😉
Having said all that though,, it all depends of the team. Some teams likes to play it clean, some love a bit of chaos, and some just wanna RP. If you get into the same mood as your team, you will have more fun.