Very nice game! I think your performance issues might come from the respawning mechanic somehow? The more i died and was brought back to the start, the poorer the performance. It also made my character's position more and more "unstable", and it would often sort of jitter from left to right, making it very hard to platform correctly and the lag made getting past mice even harder!
Still despite the minor technical issues, its a fun game visually and technically so well done to the team! its a very fun concept to play