Cool concept, decent execution. It kinda reminded me of StarFox games (in a good way) due to the maneuvering on a fixed path gameplay. The music was a nice choice- it felt relatively relaxing.
A few things that come to mind are-
1. Add a clear indicator that a missile is headed towards the player.
2. Add the speed boosts (like the ones around portal thingies) in more spots around the track, this will make the gameplay feel slightly better as it will give the players to be more active in participation of the game and also makes their maneuvers more meaningful throughout.
3. It was kinda hard to know from a distance which power-up/pickup was which mechanic. You could add a colour (maybe glow as well) to each powerup to differentiate one from the other to make it more obvious from a distance.
4. A clear indicator is needed to know how much of the race is completed / still left.
Overall, it's a decent game with good potential. Nice work, though!