Indeed. Perhaps when we learn the English names of the Unova (ugh) protagonists, you can use them as a baseline... or just remove that part entirely and just state that it happens in the far future. Either one would work just as good as Ash Ketchum, and in my experience, the less tethering you do to one timeline, the better. At least the game canon is a little more open.
I don't believe I've ever seen the Deadly Sins as physical Pokémon before. (Admittedly I have assigned a Deadly Sin to each of my fake Gym Leaders, which is why I can't use "in fanfic", but that was just for fun and I don't intend to mention that in the story itself. So yeah. XD) It would certainly be fun to watch - for me, at least, who finds that sort of thing very interesting. c: