All the talk about altering IVs in the other threads reminds me I'd like some slight changes to abilities
1. A way to switch to/out of hidden abilities. The ability capsule is already rare and expensive (200 BP! the most expensive item in the battle shops) so not being able to switch to the hidden ability seems kind of arbitrary. Almost every ability has been released by this point, too, so like...why not, right?
2. A 4th ability. A lot of Pokemon have all 3 slots filled by now, but gen 7 in particular is introducing a bunch of pretty interesting abiltiies that it would be a shame if no gen 1-6 pokemon could get them.
3. Let Levitate pokemon have alternate abilities. This has always felt pretty arbitrary, especially when Bronzor & Bronzong can have Levitate, Heat Proof or Heavy Metal. And Trapinch has a full set of 3 but it loses all of those for Levitate. I'm not saying all of them need to lose Levitate but I don't think people would raise an eyebrow at things like CYronogal, Eelektross, Carnivine, Gengar, etc