Dont forget circle of scorn!

Also, beacsue savage has a enmity modifier on it (1500 potency with SO) and fast does not, I would say Fast-> Savage <next target> ROH <next target> fast/savage.

Flash is also low threat per second, so you want to spend as little time using it as you can. It is not split up accross targets, so each will build the same amount per target. Normally, I pull in this fashion:

Shiled lob main target (marked) -> flash -> cos -> fast/savage -> change target
roh-> change target
fast savage -> change target
roh -> change target

Keep COS on cool down. If you notice the flash run out, use it just to redebuff them as a mitigation tool.

I Play on PS3, and dont' have a problem keeping all three steps of ROH combo on my main bar... so IDK. I woudln't really suggest macros for that anyway as you are not getting the best micromanagement that way (you will always have extra delay between steps than you would by using the combo manually).

If you are holding l2 or r2, hitting l1 or r1 will cycle targets left/right. Pretty sure its even limited to engaged mobs. If you can master this, you'll find you never have aoe threat problems (I can do the table top pulls in castrum before the airship encounter solo and hold all threat without problem.) PLD aoe threat isn't actually as weak as people make it out to be, it just takes more micromanagement than spamming 1.0 steel cyclone.