Very fine entry, i can definitely feel the Vlambeer inspiration in this (this is a good thing). Right now i feel like it's missing something important though: it needs more tension.
If i compare this to Super Crate Box (which i assume is kind of what you were going for), it lacks the high tension of that game where you could make a single mistake and lose at a moments notice. Right now the enemies are visible from far away and unable to catch-up or ambush you. Without that tension it makes the game feel a little mindless (and when the dice spawns out of sight, i sometimes forget it even exists).
My first thought to alleviate this would be to make the game take place in tight corridors and add something like a fog-of-war effect (if you've played Nuclear Throne, think of the labs levels: dark, tight, and with lots of weak enemies). Don't take that as instructions though, i'm not a game design whiz. Think about it and try some experiments, that's best way.
I feel like i'm being too harsh on this game though, so i just want to point out that this game feels wonderfully crunchy to play. The graphics, sfx and heavy screenshake all feel really good together. I'll be sticking around for what you do next :)