It is possible to get 3 stars on all of the maps. I know because I’ve done it.
Guide to Get 3 Stars on Any Map
Best Practices for 3 Stars
Here’s a quick guide if you’re stuck with 1 or 2 stars on a level and wanna get the 3rd.
Collect every boost
This doesn’t apply to every level, but generally, you need to go for every single opportunity to get a boost. Especially earlier in the level. Some creep up quickly, so try to remember and anticipate them.
Anticipate twist gates
Do your best to remember the order of twist gates. Fly in the orientation of the next one so you can focus on a good flight line instead of thinking about the next gate.
Take the shortest possible route
Unlike most racing games, turning quickly will not slow you down. Fly as close as you can to the inside of turns, and aim between boosts diagonally. Capture boosts on the edge so you have a shorter path to the next.
Ultimately, getting 3 stars on some of the later levels is gonna be tough. It’s going to take many, many tries, but once you get the rhythm and muscle memory, it’ll become a lot easier.