I wouldn't say the Boost formula is an example of a modern formula done right - or at least the extent of which Sonic could ideally be taken. They're fairly good games to play but modern Sonic games are more about making the player feel fast rather than allowing them to be fast - which isn't a bad thing in and of it's own, if a game feels good to play then that's a positive. But I will say that when you get so much speed at such simple moment's notice it doesn't make it feel like as much of a reward as it was in classic games where you maneuvered through cleverly placed obstacles. Designing levels for a formula like that is hard, and making them sizable enough with the speed given to you is even harder. It's why modern Sonic games try to fuse a whole lot of distractions into their game play like graphical set pieces that don't have any bearing on the gameplay or even it's story, because the games have to feel like there is something more to them.
I still maintain that the original Sonic Adventure had something of a decent baseline they could have utilized. Refine the jank, widen the levels out, allow you to curl into a ball to pick up momentum rather than spinashing at a moment's notice... you could make a good game out of that, provided the level design can back it up.
Boost games are fun but only in an ephemeral fashion. They don't really stick with me well after the fact. I have fun with them... but then I just kinda put them down and don't really return to them.
