I feel like X and Y was above average. However, to me, the pros and cons are ridiculously exaggerated.
I'll start with the characters. All four of the "rivals" felt like pathetic excuses for characters. Tierno was the worst offender by far, offering literally nothing gameplay-wise, story-wise, and personality-wise. Even in postgame, his daily event is far more inefficient than simply farming the Heart Scales off of Luvdiscs. Trevor was bad, but at least I can relate to him; as a person who (in the games at least) was always more about collecting the Pokemon than battling with them, I feel that he's somebody people can relate to, unlike Tierno. Serena/Calem just felt bland to me. Every time I saw Calem in my second playthrough, I thought I was looking at Cheren; the least they could do is give him a different hairstyle, or even a different color of hair. Both of them feel like a blank slate, which irritates me to no end. Shauna I actually found the most tolerable, unlike what others thought; she was still terrible, but she had a couple moments where I actually felt like liking her.
Other characters are a mixed bag. I HATE Diantha. Like, with a passion. She's passive, doesn't do anything to help in the storyline, her team is easy, her aesthetic feels off to me, I just can't stand her. The Elite 4 and Gym Leaders are all kind of forgettable; granted, after this long it's hard to come up with unique personalities that are apparent from the short time we see them, but they could at least put a little effort into it. Sycamore was okay, but I didn't feel like we really got a decent evaluation of his personality. I actually really, really like Lysandre. Sure, it was obvious he was the bad guy, but how was Game Freak supposed to hide that? He was the first really sympathetic villain Game Freak made (aside from N, but that's more pity than sympathy to me), and I feel like that makes him unique. If only the rest of Team Flare was like that, the story might have been decent.
That brings me to my next point - the story. I feel like the story was hastily cobbled together, honestly. It had some potential - AZ was interesting and added some mystery to the whole ordeal, Lysandre pulled the whole 'sympathetic villain' thing, and the legendaries as a wild card. When it came together, though, it felt like they just smashed everything together and called it a day. The legendaries were atrociously underplayed; unlike D/P/P or B/W, the entire story could have unfolded with little to no reference to them. It felt like they were shoehorned in. The worst offenders, however, were Team Flare. Lysandre was cool, but his team undermined every single thing Game Freak had tried to make him do. It was horribly hard to resist punching my 3DS repeatedly whenever they showed up; they were pompous, sociopathic, and their outfits just piss me off. If they had made them sympathetic like Lysandre, GF might have made the story decent; as it is, however, it feels terrible and an excuse to throw the player around the region.
Speaking of the region, the pacing was kind of screwed up as well. The EXP Share has an awful catch-22 attached to it: If you use it, you overlevel everything, but if you don't everything outlevels you. To stay even with enemy trainers, you have to turn it on and off repeatedly, which is really obnoxious. Like some people said above, the pacing had some bizarre spikes to it as well; Reflection Cave and the Fighters outside and within it were ridiculously hard to beat. The spacing between Gyms is off, too; the space between the first three gyms is about the same as the space between the next five, which just shouldn't happen. If you don't care about difficulty, though, none of that matters; the EXP Share will breeze you through everything if kept on the whole time and using even a half-decent team.
The variety of Pokemon is both a blessing and a curse. On one hand, you have insane amounts of 'Mons to choose from; on the other hand, you have insane amounts of 'Mons to choose from. It's almost too much variety; 7-8 Pokemon a route is a little overkill, as much as I appreciate it as a Pokemon collector. Everything Raikaria and DHR said about pandering to Genwunners is absolutely true; I was actually really surprised when I found out Rattata wasn't available on the first routes, or even in the entire game. The Mega-evolution issue is, I think, just a matter of popularity; most of the Pokemon people know are from the first generation, so of course they'd get picked to raise publicity about Pokemon. I feel like most of the problems could be resolved by not giving you the Kanto starters' Mega Stones until postgame; that would keep the Kanto starters from taking over one's team, and free up some space for other Pokemon if somebody wants.
X and Y's saving grace comes in two forms: The graphics and the new Pokemon. The game is simply GORGEOUS. Everything is beautiful: The overworld, the battle scenes, the trainers, literally everything. Some Pokemon's models are amazing and make me praise GF's artistic skills (seriously, Bisharp looks so badass), while others made me laugh out loud (Stunfisk). The trainers actually look similar between battle and the overworld, which is fantastic. The cutscenes are beautiful; being able to actually see emotion on a person's face makes everything so much better. The new Pokemon also impressed me. Every single one of them, even if they aren't OU viable, at least has a niche (Except Dedenne. Fuck that thing). Even things like Aurorus can be useful; Glaciate Hyper Beam will wreck most things. The Fairy typing, although helping out previous generation Pokemon more than it does the new ones, is amazing as far as the gameplay goes; my brother loves his Slurpuff, and I've grown rather attached to Sylveon.
Overall, X and Y comes out ahead. I know I wrote more bad things than good things, but that's mostly due to my ability to complain endlessly about things I dislike :P Overall, I really do think X and Y are good games for the series, and I can't wait to see where it will go next.