Okay, so this isn't finished yet, but I feel like it's one of the best things I've written so far, so I wanted to get your opinions on it.

The very last bit is how the song will end, I will be adding more to the song between the rest of it and those last few seconds. I've already written another solo for it, which will happen somewhere later in the song, but I haven't worked out how I lead into it yet.

I'll crit back anyone who crits this.
It feels both epic and empty at the same time.

The intro is cool, but it's a very common thing to hear, and to subject anyone to that for a full minute before bringing any instruments in is just way, way, way too long.

I like what you've got going once the band starts, but again it just keeps going on without changing for too long.

This is kind of the way the entire song goes, I like each idea you bring in, but it always takes too long for the next change to come about, not to mention nothing ever actually changes the song, it just keeps adding to it, which is a cool effect, and it certainly makes it feel somewhat epic in scope, but also empty as I said, since it just kind of stays there too. This effect is multiplied by the rather long section where you drop out most of the instruments.

The part where you bring the guitar(?) back in all the way up to the end is actually quite good, there are changes and direction, and the ending itself is also great.

I know there's a lot of negativity there, but I do like your ideas, but I think they either need to be filled out with more instruments or some kind of leading melody, or drastically reduced in time.

It does kind of sound like something you'd hear in a movie, or as background music to some kind of video montage or whatever, in that kind of setting this song would really work well since it is very atmospheric.
Thanks for the comment, icronic.

I should probably point out that there are vocals to go in as well. I haven't tabbed them out, as I'm pretty awful at making them sound realistic in MIDI files. They make the beginning a lot less boring. They also change from verse to chorus when the bass comes in, then back to verse again for the piano, and chorus when the other guitar comes in. These changes also make the time pass much quicker.

I'll keep in mind that the next few sections of the song will need to progress a lot quicker so as to keep people interested. Are there any other instruments you think would sound good in there? I probably couldn't add them all into the Power Tab file, but when I get round to recording it I can do a lot more.
Yeah, I could see vocals making a huge difference in how this particular song goes over, especially if you've got a lot of vocal harmonies and the like.

You might want to generally outline the vocals in the song. As you said you can't make it sound realistic, but you can still give people some idea of your melody and any harmonies you're planning.

The drums also need a little expanding, I don't recall really hearing a kick drum or any kind of cymbals in there, but I'm assuming you can't really do this since you're not working with guitar pro. Just something to keep in mind

And now that I think about it, depending on how the lyrics flow, you may not actually want to cut the song down, it's just one of those things that really depends on the strength of the vocals.

As for adding instruments in, I can't really say what'd work. I'm a guitar kind of guy, so I'd generally always pick some form of guitar or maybe a piano if I was really feeling creative. But you can use what you've already got there to add layering.
I'll have a go at outlining the vocals to give a better idea on what would be going on, but I don't have the master file with me here, just the MIDI, and it doesn't import well, so it'll have to wait about a week before I can upload it.

The vocals for the chorus are very similar to the lead guitar in the solo section, I'm using that part as a transition between the first part of the song and the next part.

Thanks for the suggestion about vocal harmonies, I hadn't really thought of that before, but they could be really useful in there. I'll have a think about those tomorrow, they could make it much more interesting.

As for the drums, I'm not really able to do much about them right now, as Power Tab's drum options are very limited. Normally I don't bother adding drums to the tab, as it gives me an extra instrument to work with, but I felt that some kind of drum line was pretty essential in this tab. Maybe at some point I'll get Guitar Pro, then I can make much better drum lines.