.. I have absolutely no issues or problems cycling through my party members for heals and dmg'ing mobs.
I find it refreshing to play an mmo without tons of addons, boring as all **** when you have an addon that tells you when to move/jump/run away rather than look at the fight/remember when things happen (% wise) - Same goes for healing and threat keeping.
If you have issues healing and dmg'ing, especially in the later flashpoints - stop trying to deal out dmg, there's 2 (if not 3) other players for that, let them focus on that, and you focus on keeping everyone alive.
Did not mean for this to be a "lolololol damn qq'rs lololol" reply, just voicing my opinion. I hope to god they don't let us make and add all kinds of addons right away.