i wouldn't say it's the worst, but i was disappointed with pok?mon x/y.
from what i've experienced with the game, i think they focused too much on the graphics and new features that they didn't put as much focus into the plot and post-game... i don't mean to brag, but i finished x in 3 irl days (which was less than 24 hours of game time) and that was basically it; nothing else to do other than battle online and get trolled in wonder trades.
the new pok?mon aren't as great, nor was team flare (my least favourite enemy organization tbh) they just kinda fell flat for me.
not to mention the exp. share >:T it's definitely a double-edged sword.
on a lighter note, i really like the idea of mega evolution (i just wish there was more of it) and character customization!
i just really miss the old glory days of pixelated sprites and whatnot! then again, i always manage to enjoy every pok?mon game, at least a little bit. i really hope the RS remakes will be better!