Overall, a pretty fun game. Other than the basic player movement, which would've taken a while to make it feel nice, I really only have on complaint with the current game: balancing. For example, I only bought one backpack upgrade and one oxygen upgrade but was able to beat the game relatively easily, and the un-upgraded player speed felt way too fast.
If you wanted to continue this idea, I think the following mechanics would bring this game to the next level.
- Adding a health bar for the blocks would add a new challenge (along with upgrades for the laser damage)
- Enemies that chase you around would add some more tension.
Of course, audio and better graphics would also be great.