Know the feeling, done a few sketches and pictures I shouldn't have worked on at the time, but one needs free time as well, right!
As far as Gwen goes i believe she can if she concentrates pretty hard, its more she needs the hands for ease of control (with it really easy with hands). Her powers are kinda mana powered manipulation of energy and matter, and her human body can best be described as a "meat suit" for an energy body. Her grandma who's far more adept had the ability to build and destroy her own body over and over around her energy body, but it was implied that Gwen was still pretty low on that skill level so by ultimate universe she could kinda make a shifted version of her body into the energy being, but not sure on the full on regen. Obviously out of canon anythings possible, just the more plausible the more suspension of belief :). Any head canon as to what shes used in or for for that negotiations?