There was a part where it did seem a tad empty (around 0:42 to 0:52) to me... I wasn't sure if it was just me (from having heard it so many times) or not though. I think I've found something to fix that up though. The part directly after that suffered similar but not quite as bad, and I've done something similar there (I'm introducing a backgroundish part synth drum at the start of those two chunks).
The repeating bass rhythm is intended to fill in as a sort of replacement for a major percussive part. Since that goes on for around a minute though... I'm going to be toning it down just a tad for parts of that first minute.
Which guitar are you talking about? There's technically two (distortion one, and a sorta muted electric one that follows the same "percussive" pattern as the bass part). I'm thinking of giving the distortion one a nice background part a little earlier than it's currently introduced right now.