Angkor Wat isn't the only temple around Siem Reap, though. I agree that standing around with hundreds of people waiting for the sun to come up, then all crowding inside at the same time isn't the best experience. But on that same day, other temples in the area (Pre Rup, Neak Pean and Banteay Srei) had at most one other small group there. And really they're almost as impressive in their own ways - Neak Pean is small but has a beautiful reflecting pool surrounding the central structure.

Same thing in Egypt too. Great pyramids are extremely crowded and you're constantly getting hassled by people selling crap. But at the less famous Dahshur area, or the less accessible Philae/Abu Simbel temples, nobody else was there and we could appreciate them in peace. For that it helped to go in the summer (low) season too.