The only way Izuku could possibly become a “villain” is if All for One becomes Japan’s prime minister and legally declares Izuku to be one.
The multiple quirk thing (is this still a spoiler? Feck it, the cat quirk is out the bag now and people should know what they are getting themselves into) does not actually bother me.
Between the Nomu and the All for One quirk, Izuku is still going to have plenty of powerful foes to deal with. His goal is to be the #1 Hero which requires more than just strength (for Endeavor, it required his competition retiring

).
As for being too far ahead of his classmates, well “man is not born equal” is literally one of the opening themes of this manga so they are fecked. Not like the majority of them have enough screen time or interaction to be relevant as personalities anyway.