Oodles of legendaries to catch, tutor moves, Pokemon Contests if you care, try to find serial codes for events, I even have some to spare, though I have a feeling only the Genesect one is still active. OR is more open for exploration compared to Sun, and you have the option to turn down instant escorts, say May asking if you want to go straight to Petalburg City. Other than that, the challenge is roughly similar to the new games, just in general Gen 6 and 7 are easy to go through. Also, find a league that may still go for that metagame, it should be kept healthy because Gen 7 nerfed too many good things.
OR, and if you're desperate for competitive battles, maybe the Battle Spot there is still active with players, Ratings is closed though.
