I got a question: Should I get a tutor now, or wait til we get Sun & Moon? I want to start playing competitive but with S&M approaching I'm feeling kind of confused.
You can always start to learn competitive, but the meta will change. Gen 6 brought Mega Evo and Talonflame. If you were to tell us that Charizard would become a crazy threat, people would've laughed lol
But, I foresee VGC/Doubles changing a lot between Oranguru, no mega evos, priority blocking etc...
For singles, I think we need to keep an eye on Wishiwashi, Popplio's evo (possible water/fairy), Ultra Beasts (don't think they'll be uber, but let's see), Pyukayu (huge threat with its ability, you may see more hazard stacking to wear it down).
Other honorable mentions are Salandit's evo for poisoning those immune to it (I think poisoning only one at a time will be it's hindrance), Bruxish/Tsareena (priority is pretty big if you look at Talonflame, M-Pinsir, Entei, Arceus, etc...) but their water/psychic and mono grass is meh typing and they don't look bulky.
As far as Alolan versions go, I don't think much will change dramatically for competitive. Raticate, Exeguttor, Muk and Marowak have some potential to rise up. Maybe UU especially unless they get huge boosts in stats and better HA.