Whoa, that's a creative concept. I like it!
I never got too far, though, mostly because it's hard to both build a reliable platform and shoot the increasing number of enemies coming from all directions.
At some point, I either couldn't properly shoot enemies below me (since the shots were blocked by the frozen enemies, or there were too many of them all around and if I managed to get them all in time, I effectively trapped myself.
I guess I would probably get better with practice, but I think it'd be worth a shot to make it a little easier, because the fun lies in jumping, building and shooting, not starting over every fifteen seconds.
As a suggestion; here's a couple of ways which might improve the game's enjoyability:
– make fewer enemies appear at once
– make the bullets slightly larger and pass through enemies (so you can shoot through frozen enemies or freeze multiple enemies which are close to each other)
– add a "special attack" (right-click) which can be activated every once in a while and freezes everything in your close vicinity.
I tried doing a "jump above an enemy and shoot below" a couple of times, but it almost never worked – the enemy froze, but it still killed me because I was too close.
Nevertheless, it's a great game, but my longest ever playthrough was only like thirty seconds, even though I really tried.