I'd love to see Cynic as well, but I assumed Glenn would not book them due to the death/vocoder combo vocals.
I don't consider Spheric Universe Experiment to be complex/tech. They're more in the standard prog metal realm to me. I realize that everyone has a different threshold or definition for complex or technical music.
Some Zero Hour tunes would qualify them for this category, IMO, but they have played the fest three times now, so I omitted them.
I realize the metalcore elements of Protest the Hero would not go over well in these parts, but they also have a large helping of progressive thrash (think Toxik and Realm) in their sound. Their songs are quite catchy as well. I love em.