I. Do. Not. Care. About. The. Tech.
Gabe, you created an obligation when you ended Episode 2 on a cliff hanger. You should have just let Marc Laidlaw and the game devs just make more games.
As long as it had kept the core writers, I'm sure everyone would be happy. Hell, any "innovation" is being handled by the modding continuity. Breadman of Entropy: Zero created a more fun combat loop then any of the HL2 games have. Singularity has a better physics weapons just by being able to use it independent of the selected weapon and making the object transparent.