Yeah, I think he could. As far we know, there is nothing that compels him to help people he encounters. I'd have to imagine the restriction not to kill has something to do with Intent.
Stormlight for me. It resonated with me and got me over some awful things in my life. The twist to Mistborn #2, and the ending to #3 was the most beautiful thing I've read in my life. I hope the conclusion to Stormlight 5 can match that.
Eh, there's no denying he's super succesful, but I still don't think he's a household name. I think you need to have a hit adaptation to really become a household name. The only exception I can think of is Rowling and maybe Stephanie Meyer?