Just a few amazing changes GF did with this game:

>Amazing 3D models and animations to make your Pokemon feel more alive than ever (No, Gen5/4 sprite based combat wasn't better than this, even if you think so)
>IVs can be checked in PC now
>You can put a newly caught Pokemon or recieved Egg/Pokemon directly into your already full party
>The game gives you 5 Ditto's with competitive natures and a perfect IV to go with them to get you started nicely on your breeding adventures
>The daycare girl giving you eggs doesn't glitch out like the ORAS equivalent would sometimes

>SOS is superior to things like DexNav search for obtaining good IV Pokemon and Hidden Ability (Remember when you tried to chain Bagons in ORAS? Or Gible?)
>Game gives you multiple, some infinite, amounts of some legendaries, most of which are competitively viable
>HM's removed to make your life less annoying
>Varius battle changes to make the game less stupid like Mega Evolution now using the speed of the Mega to decide who goes first in the turn
>Finally you can maximize the potential of any shiny/legendary, no need to reset the game a million times to get that flawless Thundurus (Actually you still do this because HP Ice maybe but its an exception).

Yes the cutscenes can get annoying at times, but other than that, USUM is a 10/10 game, the best Pokemon game to date, and you should stop complain and maybe try play the game.