The ability to increase IV's manually - even if it's difficult to do - has always been one I'd hoped would make it in to the games. The optimal strategy for breeding has some rather unfortunate implications that have already been discussed over the past few pages, and even if you don't have a problem with that there's always been something disappointing about knowing that your in-game story-mode team will never be competitive material no matter how much effort you're willing to put into it. Even if this route turns out to be harder than breeding and can't be used on legendaries, I'm very glad it exists.
Creating our own custom challenges looks interesting, but it will need significantly more options before "Smogon on cartridge" becomes an accessible reality. Whether or not we'll have the ability to choose 6v6 battle format and create custom banlists remains up in the air, but if it does happen that'd be very cool... and potentially open up a nasty bag of worms with regards to event pokemon and moves. Up until now the exclusivity of these pokemon hasn't been an issue for the sim-based community, but if a number of us start playing on cartridge those pokemon will become very exclusive. Metagame defining threats on simulator might be virtually unheard of in cartridge play just because no one has them, and that will mean you'll get two very different metas. Could be a huge problem, but that's presuming we actually have the tools to make it happen.
As for the pokemon, I'm really happy to see all the new abilities popping up. Having generic abilities that are shared with a dozen other species can quickly make a pokemon forgettable, but a unique ability can really make a pokemon memorable even if it's not actually that great competitively. Everyone remembers Furfrou and what it does even though it was a total flop. Even garbage like Plusle and Minun are more memorable for their unique gimmick than other pokemon with more practical but boring abilities (oh gee, another electric type with static). Everything revealed so far looks to at very least be interesting, and that bodes well for memorable pokemon that we'll know and love for years to come... even if it's only in a lower tier.