I set up my F1-5 keys (disabling them on other toons) on my healer to cast heals on party members 1-5 with a cast sequence /cast hot /cast bigger heal. So basically 1 click of F3 to drop a hot on toon 3, if I hit it again it drops a big heal. If the party is taking ae damage I just rotate through F1-5 to give them all some hots. I have a full cast sequence on my F2 keys which is normally the tank being group leader which rotates through 4 heals (is a resto druid).

I use clique on my tank so if someone rips agro I middle click their toon in grid and it auto taunts on that person without changing target.