I've been fighting Susanoo alot, me & a Fellow guildie have been talking and I've been trying this. Starts off with 5 Chakra stacks, fist of fire & Coerl Form (Duh)
1) Shoulder Tackle > Demolish > Perfect Balance > Snap Punch > Snap Punch > Dragon Kick > RoF > Twin Snakes > Internal Release + Forbidden Chakra > Snap Punch > Brotherhood > Bootshine > Howling Fist + Steel Peak > Elixer Field > True Strike > Demolish > .....
I've found that with ROF up you can double weave oGCDs inbetween attacks.
I've been considering saving internal release until ROF is down so you can get the most GCDs in with it as a way to boost Chakra gain after ROF + Brotherhoods generation go down that way you'd have 35 seconds of heightened chakra generation from the start of the fight. Also been thinking about using tornado kick at the start of the fight near the end of ROF once I get to 3rd form since alot of buffs will be running out near then the burst of damage might be worth it but not able to tell yet.