I usually love Sonic's cheerful upbeat music, but I'll give this a try since it fits the environment.
I don't mind the PSO2:NG-vibes since PSO was first created by Sonic Team afterall.
Now let's wait for the combat battle.
Based on the teaser, one of his new attack's like from Pac-Man World 3
(running around the enemies to destroy them).
Let's see what's more.
Sonic Frontiers: Combat Gameplay Trailer | IGN First
https://www.youtube.com/watch?v=q88r4mKJGoM
I think an elaborate combat for Sonic is a good thing. We haven't had one of those since Shadow's game (and Sonic Battle and Chronicles I guess). In almost every Sonic game, you just jump on the badniks. Homing attack just makes it all the more easier to the point badniks are treated more like obstacles or stepping stones than a threat.
My guess for Sonic Frontiers is Dr. Eggman finds a whole armoury with alien robots and all he had to do was run his badnik loyalty program through them to take control. He'll probably still make badniks in the game but these enemy robots look nothing like Eggman's designs.
