I think the biggest problem that this could have is the pacing, and I think you know that. You do have lots of subtle details though that ultimately I'm okay with the pacing for the most part. Some suggestions/observations:
- What if you added a slight filter envelope on the choir-like pad you start using in the beginning?
- Is there any way you can make the bells near 1:27 more tonal? Or are they just something textural for the background?
- The repeated bass pattern repeats a lot. That's really what I'm most concerned about. But you do have some variation on the bass in the second half which helped (for instance, near 5:10).
- How about a space-like sweep at 3:24 if you have one? One example I can think of is the one used for this track at 0:21. I heard some sort of sweep there, but I think it could be more obvious. The later instances of that sweep you have now, though, I would keep, though maybe you can thicken the tone up a bit with some slight distortion?
- 3:59 can have a transition, so some sort of long reverse can work (like a cymbal, noise sweep, etc), and whatever else you may think fits if you add that reverse.
That's all though. It's improving!