I don't know if its just me, but i struggle to make a gap between myself and my attacker as Disc mostly, and shadow to a lesser extent. This usually results in not being able to get a decent heal off, or most of the time having to eat an overpower or try and fakecast a kick and a team mate going down as a result.
My suggestion to help priests out of this problem is to change Glyph of Fade to the spell in the Shadow Tree plus a little extra i.e.
Glyph of Fade- Your Fade spell now removes any movement impairing effects and makes you immune for the duration.
A little hand of freedom on an identical(?) CD.
The Shadow Tree would either have to have the spell removed or a different effect put in its place, to this im not sure, Maybe 10% more avoidance when popped? Shrug