Alright, first of all, you gotta compress those files. .aif is raw, uncompressed audio. Basically the same as .wav files. Compress it (i.e. turn it in to an mp3, or mp4, or whatever). 42MB is way too big. But that's a small gripe.
I like the intro a lot, but it needs a little more movement. If it were me, I'd add some kind of sweeping sound to what's already there, or maybe a light cymbal (but not all quarter or eight notes, syncopated ... be subtle ... blend).
Verse 1 Part 1: I like the lack of drums, but it still needs a beat, I think. Maybe just the cymbal, no kick/snare.
Verse 1 Part 2: Drums in -> Good.
When the drums pick up, it's really good, but the phasing on the guitar gets just a little snarky. Maybe lower the speed of the phase, to reduce some of the "seasick" effect it gives. Especially in the solo, later. And I'm not 100% sold on the drums getting even faster over the solo, but maybe that's just me.
Let's talk about intensity.
The volume is better, but it really jumps up at the solo. A lot. I read something a few months back, and learned that volume changes in songs, like builds and things like that, aren't actually all that drastic. They SOUND drastic, yeah, but decibel-wise the change really isn't that great. What's REALLY changing is the intensity/velocity. How fast or HARD the instruments are playing, not necessarily how loud they are. Think of it like a piano. Yeah, the harder you play it, the louder it is, but that's live music. In professional recorded and mixed music, a piano playing at forte will be pretty much just as loud as a piano playing triple forte. It only sounds louder because a piano sounds harsher when it's played at triple forte, it has that scratchy slamming sound to it. In actuality, they turn the volume UP when it's forte, and bring it DOWN when it's triple forte. This keeps the instrument audible at all times, and maintains balance, but you still get the impression that it's louder.
The same can be said of drums. You hear a snare build in your favorite song, the drummer banging on the snare louder and LOUDER AND LOUDER. But if you took that mp3 file and opened it up in some sound recording software, you'd see that the snare it's actually GETTING much louder, it's just being played HARDER. If anything, the volume is being lowered as it's being played harder, but it's so subtle you can't (and shouldn't) notice.
So my suggestion to you is to experiment with some of the other instruments, adding intensity by making them play more notes (especially the bass), or by increasing the velocity of the notes to make them "harder." Do this, and try to make the overall track a little more equal in volume. It doesn't have to be uniform, but I think you have just a little too much disparity.