Pokemon Sun and Moon are eons above pokemon X and Y. If you're into subtle details, you can take into account the new animations, idle movements, how there's a small jerking motion when your character stops running or moves from a run to a walk. If you're into bigger details, there are a lot more pokemon, and it reminds me a lot of the first generation without being too much of a throwback. There's just enough there to feel nostalgia without them pushing it too far, I literally fangirled over there being a representation of the nugget bridge. It's kind of story heavy but the story is good, especially by Pokemon's standards. This game is definitely worth all the hype people were giving it, my only pet peeve is the fact that you only get one of certain stones, (ice stone, sun stone, and moon stone) and have to play through poke pelago to find more, or get another copy of the game and play through that to get another one. It makes it hard to fill the Pokedex if you aren't willing to trade too much.
Even if the new pokemon shown haven't enticed you, there are quite a few hiding that may become favorites once you look into them more. Pokemon like Dewpider and Mareanie come to mind, they weren't shown in trailers and haven't really caught much attention from fans, though they have quite amazing designs. If you still don't like many of the new pokemon, don't worry, gen 1 through 6 pokemon are available from pretty early on in the game. You can even catch Magnemite on route 1, as well as Pichu, caterpie, etc. There are plenty of other things I could point out, like the Festival Plaza and such, but I'd rather leave that for you to explore, after all, a game is no fun if you're spoiled about everything!