some things to remember about peach: short hop to a hover on the ground, this way u can use your great air moves at ground level. fast fall this move. peach's forward throw is amazing. at 100%, it can kill the characters in the lower weight bracket. her down smash is insanely prioritizing and has hidden range. its great to edge guard with, but an even better edge guarding tool is her aerial back +atry to tip with her fair while short hovering. easy way of accomplishing this is to C stick it and then move back ward fair = forward air. some times with a good coordination with short hovering you can fast fall a back+ a and follow up into a grab. this calls for a seasoned short hoverer though. but remember you will still have a hard time against marth because of his disjointed hitbox. hold down then hold X to short hover. a standard jump will suffice (for the lazer)