Here is the rotation i use on 2 targets or less (IE the boss).
Code:
/castsequence reset=combat Mangle (Bear)(Rank 5), Lacerate(Rank 3), Swipe (Bear)(Rank 8), Swipe (Bear)(Rank 8), Faerie Fire (Feral)
/cast Maul
I dont use Imp mangle. Mangle comes off cd just as i reach it in the rotation. The rotation is based around FF and Mangle (neither of them are off cd for more then half a second throughout the duration of the fight).
Ive never had any problems with this rotation. I often find myself slowing down because Id be pulling threat from an off tank (Torovan, precious, fights where 2 tanks stand in front of the boss).
Depending on the situation, you may want to get up to 5 stacks of lacerate first. Other than that, swipe's damage is more threat than Lacerates front end damage.
Just... no. If you do that and you don't have enough rage for a few seconds (You know, those dodge streaks), you'll try to do maul when it's not possible, which means you're losing out on maul and white damage. Just place maul on a button that's easy to spam.
Rage is never an issue for me, ever.. except maybe, maybe on some, and i mean some heroic 5 man dungeon bosses, and all my macros have /cast maul built in (meaning im using maul every time its possible).
Spec and Gear in armory link