I really have avoided any personal opinions on ORAS. The reason why is because I am probably one of the only modern Pokemon fans that dislikes the games. The reason why is because of a lot of things. Though, if I just have to skim through a bit of the stuff, here I go:
-first off, I am not really a fan of the selection of Pokemon from Gen 1/2. I wouldn't mind this normally, but since it was impossible to incorporate any sort of link functionality between GSC and RSE, I feel that the region had no excuse for bad selection. And speaking of available Pokemon...
-...some of the new Pokemon are kind of meh. They aren't as bad as some of the other Pokemon that I hate, like Ambipom, Electrode, and Raticate, but I still find that they just aren't very memorable. That being said, though, Hariyama, Flygon, and Torkoal are all awesome.
-The sound is pretty bad, especially for GBA standards. I say the sound, because most of the tracks in the game, such as the Frontier Brain battle theme and Champion theme I really like. The soundfonts for each song just feel really tinny and unrefined, and it isn't like the hardware was holding Game Freak back. Just listen to things like Mega Man Zero 4 and the Sonic Advance games. They have great instruments!
-The whole atmosphere of the game felt off. I guess it is cool how everything in the game is themed off of Water, Earth, and Air, but it doesn't really mesh well with the Pokemon formula, since combat is themed around elements as well.
-Also, most of the character designs are pretty annoying to the eye and don't really fit the rest of the games theme.
Now, for things in ORAS that I am genuinely excited for...
-The graphics all look very nice. The animation with May when she prepares for the Rival Battle is especially well done. Everything just feels quite cinematic.
-The new Megas, while containing a few duds (Slowbro, Audino, Latias/Latios) are pretty cool (Beedrill, Sceptile, Rayquaza)!
-The use of MP3 audio on 3DS means that the songs in RSE can finally get the justice they deserve.
-And finally, Mega Luxray maybe?