In PVE I love my shadow priest team as well, running with a DK tank they are pretty damn strong. Like you mentioned, some of their cooldowns are on quite outrageous timers.

The mind spikes and a mind blast + paralysis crit, death, death definitely forces a bubble, if you get someone that is asleep you just decapitated a player.

When the patch dropped that Mind Sear could be targeted on the tank, a lot of encounters got stupid easy. While its not the strongest AoE, its now at the full duration.

How do you have your character's glyphed?