Really? Some of these leaks have made me more excited for the game tbh. I'm not completely down about the entire dex situation, because I've always felt it was unrealistic to have so many different pokemon living wild in a certain region.
I agree with this! I actually liked gen 5 since it was new Pokemon only, seemed so much better to me and I really wish they'd kept that up. Have like 75%+ new Pokemon with maybe just a few from previous gens mixed in here and there. Lately they've been having way too many previous gen Pokemon in the new regions and I think it just dilutes the experience of having a new region.
Plus, as you said it's definitely unrealistic. Just look at the real world, how many animals are actually shared by different countries, especially countries that are no where near each other, or those that are islands (which is most of the Pokemon regions actually). Even those that are shared are often different still, so regional forms were a great addition, just wish they'd come sooner and not been exclusively for gen 1 Pokemon before.