Hmmmmm. Don't need to move the feathers to crest. Usually, one crests first, and the feathers are put on later. Of course, if you want the feather fronts or backs to meet or be a certain distance from a cresting line, you might need to move them a bit, or, move your cresting a bit.
Regardless, another half-inch forward won't make noticeable difference. It will provide more clearance for your string hand fingers. I'm surprised you're not already hitting your fletching with your fingers while nocking if currently the back of the fletching is 1/2-inch from the nock. Not a biggie on the range, but tickling the feathers with your fingers can make enough noise to spook a nearby critter. Good luck.