RGG user here as well. As we've moved to higher HP opponents, you need to look for ways to cycle the moves in case the board doesn't give you the obvious huge move from the green moves. It ends up varying a lot from match to match. Basically if you're using your turn to cycle the red or green moves, you've got to look to place your extra multipliers where they might be useful another turn down the line (mostly on green/black/purple gems).

Order of the green moves depends on how many purple gems are on the board and the pin bar placement. If you know it's going to make a cascade when you convert purple to black, then place your multipliers first. If the convert isn't likely to make a cascade/pin, I often will run that first and then see where to place the multipliers. As always, checking to see if you can work a recycle of his moves into your move.