Throw some GP3/4s into your slots.

The real challenge is hitting 700. I think the only way to do that is 2star accessories and 150 leftside with maximum GP slotted into everything.

700 lets you do several things though; Like 3x / 2x gathers combined with hq / gather chance, or 2x gather with +1 gather chance.

650 is a safety break point bu t700 lets you get real greedy