Thank you for playing and also thank you for your feedback
1-The amount of bullet spawning is somewhat luck-based, as the spawning interval varies between 2 and 7 seconds. Enemies' spawning intervals vary between 5 and 10 seconds. However, the bullet spawning interval can be reduced.
2-You are quite right about this because the character moves based on degree, as the radius of the ring decreases, the linear speed decreases. It was added to the list of bugs to be fixed.
Hope you have more fun next time in the next update. Best regards