Anything from "Another Won" to "Raw Dog"
Even though this is the least helpful post in the entire thread, it's a nice one that I really approve of.
On the other hand! Based on the OP's tastes...
You seem to really like the epic stuff - in mood as well as length (6DOIT, Metropolis, Octavarium) - and the slightly modern stuff; The Great Debate particularly having a bit of a futuristic synthy edge.
So on that basis, I'd say The Count of Tuscany is probably a must (and the closest you'll get to a bastard child of Six Degrees, Metropolis, Lie, The Great Debate and Octavarium!). Erotomania is quite a good kinda... hybrid between Metropolis and Lie, almost. The technicality of Metropolis but it's got a kinda straight-forward rockin' style to it, and some really memorable melodies. It's probably worth giving The Mirror a spin, too, as it's Lie's slightly-older sister, although it's not nearly as catchy as any of the other songs you've enjoyed. Aaaand, Blind Faith always kinda falls into a similar "genre" of DT song, for me.
So, yeah. The Count of Tuscany, Erotomania, Blind Faith, and possibly The Mirror. Seems a good way to continue.