Well, it certainly has the alpha feel going on -- Rifle looks sharp and the HUD works great. Not bad at all, though I do have a few thoughts:
- The Alpha Demon animations need to go. They look very unfinished (mostly because of the fact that they are) and don't fit at all -- I think this is one of the things it's safe to say id would've 'fixed' even if they'd went in a direction closer to what the alphas show.
- Ditto on the music. I know it's an old 'unused' Doom tune from Prince, but it's too obvious a cover (STP's "Sex Type Thing", just to prove I know it

) and doesn't fit at all. Really, it seems to be in the same vein as the aforementioned demon animations: The 'unused' music is just another set of Alpha resources that had not yet been finalized but would've gotten 'done' regardless of what direction the game took. I say the original tunes would probably fit best here -- for now, at least. If you want different but Doom-y music, there's sure to be at least one talented MIDI composer out there who might be interested in lending a hand.
Having said that, and realizing that everything shown is unfinished so far, I do like how this is shaping up otherwise.