Really loved this. You have some really nice ideas.
Some things you could try for next time:
1. I think you should vary the drums more. Right you have basically two different beat patterns, and you only switch to one of them for a short time. Drum tracks are one of the most commonly overlooked parts of pattern based music, and taking the time to make it unique can really add a lot to your piece.
2. You can try varying your melody more -- this one is really your choice though. For credits music it's probably good the way it is, but there are a lot of sections that don't seem to be moving anywhere because they don't have a strong melody. I'm not saying every section of your piece has to have a soaring melody, but adding in some melodic elements in some places could help some.
Altogether though, really cool, and I saw it as more of a credits theme myself.
- CS