My HM Slave, who NEVER personally saw the light of combat once during my initial playthrough was level 87 by the time my first run through of the game was finished.
Christ dude. No offense, but that sounds like a you problem. I fought nearly every trainer I could throughout the game and my event Blaziken (that gets faster EXP growth due to technically being "traded"), which I used frequently, barely broke level 70 by the time I beat the game. And that was with EXP share on the entire game.
All right, you got me. I guess during my first playthrough my team saw a LOT of restructuring to accommodate for some of the things i got via Wonder Trade like Gale Wings Fletchling and Protean Froakie, so that might have added to my HM Hawlucha being a bit overleveled. that, and I was trying to regularly go back and do Battle Chateau, which builds levels and money with how many battles you have to do to make it to duke/duchess.
I suppose EXP share and the changes to the EXP table are relatively small pickings compared to some of the more egregious things about Pokemon X and Y such as the frame rate that constantly shits itself, the wishy-washy use of the stereoscopic effect, the bizzare decision to have 4 characters performing the role that 1 well developed one used to do just fine,
Whatever the **** Lysander's plan was and the whole of Team Flare being stupid, the lack of new postgame areas besides Kiloude City and the really sly way that they tried to make it look like you were going to be able to ride your pokemon, but instead they just made 3 REALLY tedious gimmick routes where you have bizzare tank controls on a grid.
Not that they're bad games! Gamefreak are masters at their craft! the fun is still there, and everything they have on the bottom screen is AMAZING! if there are not at least equivalents to the PSS, Super Training, and Pokemon'amie in future games, they will have dropped the ball so hard. Especially the PSS and it's extreme ease of trade with things like Wonder Trade. Wonder Trade is especially amazing as it's motivated me for the first time ever to try and fill the pokedex. It also has me turning on my Pokemon X version every day, as having SO many pokemon with different Original Trainer IDs means that I pretty much get something from the lottery every day, which until this gen, I thought was a vestigial organ left over from GSC. There's also so many little time savers here and there that give people who naturally breed their pokemon a heck of a lot more of a chance competitively then those folks who just bought an R4 and saved themselves the trouble by save editing in a perfect team to play some multiplayer with.