My suggestions:
For the first set of turtles, have your best ranged dps pick a turtle, and have all the other ranged dps assist off him or her. That's by far the easiest way to get the first turtle for kicking.
Have a designated turtle kicker. It takes some time to get the timing right on the kicks, especially from a distance. So make one person do it constantly. Big survival cooldowns are a huge plus here, as you occasionally have to stand in rockfalls to get a kick off - I once had to soak 5 at once to get a kick in. No one else should ever kick a turtle unless the designated kicker calls for it - they may have plans you're not aware of.
Set up a cooldown rotation for the stomps/rockfalls.
You really only need 2 dps (10 man) to handle the turtles after the first one, so put everyone else on bat/Tortos duty.
In my experience, an immediate bloodlust works better than saving it. Everyone, including the turtle people, can full burn on Tortos. That makes the middle part of the fight much shorter (and therefore easier), and the turtle-spam at the end just isn't rough enough to make it worthwhile. Your experiences may differ, but that's my take.