Needs some work.
I didn't really get the alphabet tie-in also there really isn't much variety. I played it three times and it seems like every time I played it I eclipsed zero on time at about the same time I would pass "Wildstyle". This was shooting everything that was coming my way and not letting a single object pass while transferring energy to time. Shortly after hitting that point both my energy and time were in the negative numbers.
I think you have the timer set to run too fast. Either that or you're not allowing the player to recoup lost time or energy fast enough by sending them enough things to shoot. Also, the game needs a definitive "game over" as even though I went into the negative on both energy and time, the game kept going for a few minutes before the letters and colored asterisks stopped falling.
Kind of dull overall, but could have some potential if you find a way to really tie in the whole alphabet idea and improve on some of the things I mentioned.
btw, I know you mentioned that is still has some bugs. I'm just offering some ideas and opinions here.