Nice one. I hit a bit of an issue at one point where all your enemies would get stuck together, obviously doesn't impact the gameplay at all. I know from working with (Unity) navmeshes and agents that this can be a pain to tweak.
Took a while to figure out how to activate the power pills but figured it out in the end - and as an old fogey I like having to use my brain rather than being told what to do :) Liked the mechanism.
Also a tiny other thing: it would have been cool if the tunnel worked - from experience, nav agents do NOT like being teleported though so you'd need to disable it first. Can't remember if the ghosts in Pacman use the tunnels though...