People often say how it "wanders" or has "filler" parts to it, but each piece is long enough that moving from highly structured to improvisational and back is fine with me. I actually like the less structured parts, and the way everything flows is really cool. I wouldn't change any of it.
Okay, maybe the ritual part of "Ritual" (starting at 14:20) could be shortened up just a bit, though I'm not sure how. It's the only part that ever feels to me like it goes on just a bit too long, but I guess it's supposed to be like that, to build the tension. It's not so bad now, I guess; about 20 or so listens ago I finally realized that the pattern played by the drums and that brash, almost atonal synth (at 15:57) is really one of the main musical themes. It's so far out there that it's pretty hard to tell. The ending is just glorious, though. It wouldn't be so awesome if the preceding section weren't so chaotic, but sometimes it taxes even my patience.