Usual de-powering sequence

1, Downhaul to max, once you are still overpowered
2, Move rotation from pointing at the shroud to pointing at the outboard end of the back beam, once you are over powered
3, Move the traveller out, once you are over powered
4, Let the mainsheet out

You will also need to play the mainsheet as you cannot (usually) react quickly enough with mast rotation or traveller, so in reality you set 2 and 3 as a course setting and then play the mainsheet, if you are letting too much mainsheet out, you need to revist 2 and/or 3. Also note, when playing the downhaul, this twists of the top of the sail making it flatter, you then MAY be able to sheet in harder again now to reduce drag while keeping the same power.

You may also (as you say in the initial question above) move the jib cars out etc.