Pretty neat. Surprisingly legible.

There may be some call for the option of a "barred I" for uses that want total monospacing, or for the isolated word "I".

The stroke weight across the bottom of the ampersand is unusually shallow.

I might suggest differentiating the zero as a closed loop with an isolated stroke in the middle. And close the loops in the percent too, because really, what are you even hoping to do there.

Cyrillic П is not likely to be recognized at all. You're better off inverting a U for that.

Greek is begging for a lowercase omega. Also consider the advantages of a lowercase lambda.

Hi! Thank you for your time and your helpful advice. I utilized most of it as seen here:
I was actually thinking at times about the barred I, but I didn't get to it before. I know this one is a little creepy, but it's the only way I could think of.
I'm a little unsure about the 'lowercase' omega and lambda. I like them on their own (esp. the omega) but since I don't know Greek I have no idea how they would work among other 'not-so-lowercasey' characters. I can only hope they'd do just like their Latin equivalents. One thing that could be done is further case diversification.
I'm rather reluctant about the П though. Do you find the Greek pi unrecognizable as well? Whenever a glyph needed an extra stroke to fill in the whites, I seeked inspiration in handwriting, despite the somewhat technical/industrial appearance of the face. I thought it worked well for these two. I'm aware I might be alone in this belief, but wouldn't basing the П on an inverted U make it too easily confused with the capital lambda?

Handwriting, glad you mentioned it. Cyrillic cursive and italic forms have a number of interesting peculiarities, and among them is that "п" becomes "n". So I meant to flip your "u" as it is, and the resulting "n" with the stem preserved may be the clearest possible solution. What you had was really an "л" with a swash, which is not unheard of. You may get a number of other useful ideas by studying Cyrillic handwriting, and also a thing called vyaz, which is a historic kind of decorative space-filling blackletter.

As for the Greek "π", it is decipherable, but consider squaring off the top, and perhaps even mirroring it entirely.