Thank you very much! I'm so glad you approve of my design decisions. :') Yeah, the red blocks' physics wasn't in my original plan, but then I was like, "What if physics... and chain reactions... Yeah, that seems like a good idea."
The un-slow-down-able speeds were not intended, but when I noticed them happening, I was just like, "Oh, sure, that works. Let's leave that."
(I did make one tiny tweak of stopping the red blocks from following you around once you're invincible, just so you might still be able to dodge out of their way once you're moving at high speed, but still left them aiming towards the player by default when they spawn, just in case the player wants to continue blasting through them all... y'know, for fun.)
Glad you liked it!