Maybe a little too varied.

The intro is okay, and I like the drum fills, but they almost feel a little too much, compared to the guitar. Nothing too bad, but it wouldn't be my first choice of drum rhythm.

The bass comes in at 0:14, and to me it sounds way too fast. The guitar is playing so slow that it makes the fast drums and bass sound completely out of place. The drums also sound a little random. Variety is good, but as a listener, I also want to hear some common rhythm. Now, if this was played on a real drum set it might sound a little better, but as the midi it sounds too harsh.

At 0:30 it gets a little better. The drums are actually good here, aside from the weird rhythm of the snare (it sounds off beat to me). They fit the heavy metal genre really well. The guitar is pretty good here, and I like the bass a lot better then in the beginning.

From 0:36 - 0:43 the drums are perfect, and I actually like the use of the tom at the end of this section.

The rhythm completely changes starting at 0:44, and it works pretty well, but I would either take out the drums completely from 0:44 - 0:52, or use a much softer rhythm then what you chose here, like the one drum beat that come in from 1:03 - 1:06. That right there is perfect and would go great with the whole soft/clean guitar part.

The clean guitar is a really nice change and I feel it fits the whole track really well, and even the bass fits with it. The only thing I don't like is at 1:15 it just sounds a little weird. I think it's the way it sounds like you just switched guitars halfway through the bar. It's not horrible, but like I said, it just sounds weird.

I don't like the speed up of the kick right after the final clean note. It sounds out of place compared to the rest of the song. The section from 1:22 - 1:35 is okay, but nothing too fantastic. It just sounds like it doesn't fit since the track is so random.

1:36 - 1:50 is my favorite part of the song. Absolutely nothing wrong with this section at all and it's very catchy.

The weird instrument that comes in right after this part sounds, well, weird. It sounds like a sweeping piano almost. I just don't think it fits with the rest of the song in my opinion.

I'd have the guitar fading from 2:00 - 2:07. It doesn't have to fade completely out, but it would make it sound a little more realistic. The picking instrument here is really good, and makes for a good lead. I'd also end on a different note. The one you chose sounds really flat, and makes the song sound unfinished.

Overall, to me it sounds like you have a lot of good ideas, but you're cramming them all into one song. A lot of these riffs could very easily be their own song. You have the right idea though. Try writing an entire song using just one common riff with slight variations instead of a bunch of different ones.