
(wait, that death counter can't be right... I was sure I died a lot more than that.

)
I've now accomplished as much in the game as is possible in this build, and at this point my praises are many, and my criticisms are few.
Someone else mentioned problems with the sound in another thread, and I have to agree. You picked some GREAT music for this game, but only getting to hear the first 10-15 seconds of the song over and over again, interrupted by the repeated sting of the "death music" frustrates me to the point of turning the sound off more often than not. You mentioned removing the "disable sound" feature in the final build to correct the glitch where collecting a unit with the sound off freezes the game. If you do this, I highly recommend changing it so that dying doesn't interrupt the music. I don't know why, but it makes dying repeatedly a million times more frustrating.
Also, and I don't know if this has been brought up before or not, there are some places where the audio levels can be a bit iffy. It seems like the music is at a normal level on one screen, and then blaring loud on the next. Two examples of this are when you pick up Mike Tyson's unit (that... doesn't sound wholesome) and when you hit the Tetris screen. It's pretty jarring.
Other than that, though, the game's pretty much perfect. The boss I had the hardest time with was Mother Brain, and the easiest one for me was the Clown Copter, but I think the bosses are balanced really well, and I wouldn't change anything about them (except to fix glitches and whatnot.)