It's too easy to just crutch on your healer(many people never use anyone else once they get a healer, even if they don't particularly like the character of their healer), but like I said before, there are definitely times when you want to use others. Hell, my Trooper-Vanguard loved using M1-4X at times just to see 2 tanks barely taking any damage. Sure it took about 5 times longer to kill foes, but we never got seriously hurt. :P
"Sir,we are beginning our search for these rumored 'underwater villages'.They will not stay hidden for long". -Battle Droid Commander OOM-9!