I want a rival that hates me, pushes me against a wall, and tells me he's going to burn my dreams to the ground
You were basically that to your rival this time around.
My issue with this "paradigm shift" is that there was really no believability to it, given the fact that our character never speaks a word. (Unless you count the two-choice questions as speaking, but those were few and far between if I remember correctly.) I guess, if the roles were purposefully supposed to be switched, our rival was portrayed reasonably well because I was aggravated by them every time they showed up, from the very beginning. But on the other hand, there just wasn't anything to make me care about the relationship, because of course the player is going to raise their Pokemon well, play with them in Amie, etc. etc. Just because our rival got a lot of dialogue about how they lack self-confidence doesn't turn us, the player, into the G/S/C rival or even Blue, because we have no opportunity to really show our personality outside of those limited two-choice questions. (Heck, I would've liked to run away from several of the big friend conversations, but of course I was unable to do so.) In terms of all our friends, there was no real "opposite" to the stereotype of "earnest Pokemon trainer". Each one of our friends had that quality - they just showed it in different ways and had varying degrees of talent. To me it was slightly weak in comparison even to B/W, because at least Cheren was focused so much on being strong that he rather forgot about the whole "earnest" schtick.
So yeah, I didn't really care for the rival (or the friends) dynamic myself either. My main problem is that the rival, and each of the friends, seemed ripped directly from a light-hearted anime. And while I don't normally have a problem with those sort of "archetypal" characters, it's different to see these characters on screen (and have the benefit of a fast-forward button if necessary) than it is to have to interact personally with them in a game. I don't play any Japanese games aside from Pokemon, so of course I can't speak for how many imports have the "anime quality" to them, but I've always felt that in Pokemon's case, it needs to be done carefully to keep from becoming boring or, worse, dis-likeable. In this case I think it was unfortunately done to the extent that it became the latter. I personally had no patience for any of the friend/rival cutscenes, especially when they took that inevitable turn into "it's so wonderful that we're friends, we all have to try our best, let's never stop being friends" territory. But then again, I probably shouldn't be analyzing this much, since Pokemon has never been a series that runs on character development. xD
Otherwise...I still don't care for Lumiose City, but I have been slowly getting used to it and I've at least memorized the important locations, so that's more of a mild dislike. Another mild dislike is the "you must wear a hat" thing, which I don't get and would like be exempt from.
I also feel like it's difficult to level up once you hit lv.70 or so, which is frustrating. In particular, I'd heard a lot of good things about the Battle Maison and was looking forward to it (although I hadn't read about its specifics) so I was slightly disappointed to find that it was another one of those Battle Tower-esque places that don't give you EXP. (And yes, I know that you get Points and trade them in for items and all - the issue there is that I'm too lazy to go to the trouble of battling if it's not going to earn me anything right away. xD)
I disliked how the Team Flare story was built up. Though I respect the storyline itself, I feel that it could have been expressed differently and laid out on a more even keel. Also I felt that Team Flare had no real menace, even when their true motive was unmasked. I think that comes mainly from seeing full-body renders of the team members and getting the full effect of their "mod" poses, whereas in the past, teams were just represented by sprites, with no campy stuff aside from the occasional bit of comedic dialogue. It's fine to have a few blundering goofballs in a team, but in this case it felt like every single one of them were that stereotype - and although that makes sense when you think of how team members joined, it also takes away credibility from their motive at the same time. Double-edged sword, I guess.
Other than that, I can't really think of anything. My postgame play is mainly comprised of getting items from the Amie screen, playing with my Charizard and other Pokemon, and battling in the Battle Chateau. It's at least keeping me interested for those things, so I can't say it's as disappointing as other postgames, some of which just made me drop the game entirely until I was ready to restart the story. I have no complaints in terms of graphics or mechanics, either. So even if my post seems more negative than others', I really do think this generation is the best since R/S/E.