you haven't proved that peter can use more than one power at a time you proved that a version of him that does not exist can do it five years from now. Just because a person can do something with their power does not automatically give Peter the same feats, he copies powers not skill, if he does not train to use the powers like the people he got them from then he can't do anything beyond the most basic things. Claude taught him how to use his original power, not any of the others, the only things they practiced were tk (which happened by accident) and invisibility. Where do you people get the idea that just because he can regenerate damaged tissue that he can come back from being vaporized which is just a short way of saying having his molecules dispersed, which is usually the only real way to kill anybody with regeneration (Eternals, gods, etc...).