I get what you're saying, because I feel the same way. I remember when I first listened to the album, I caught myself multiple times thinking "Wait, this is still the same song?" Sometimes I felt like it was too progressive for its own good.
Keep in mind that I don't think it's a bad album, just adding on to jd091's post that it could use some improvement.
2.2 Unpure / Infinitum Obscure / Volahn
2.13 Volahn / The Haunting Presence
4.5 Antaeus / Demoncy / Volahn