I've played the "shockcadin spec in season 6 and a little bit of 7. It is a viable spec, it is very nice in 2s because it is so easy for you to kite/LOS just about any class. I hate not having persuit of justice or the free stun trinket. Not to mention you give yourself replenishment so that you have unlimited mana without ever having to pop divine plea. I even used seal of light with this spec because the heals are kinda gimp since you're not full holy and the crits aren't big like when you are prolly and since you have no mana issues there is no reason not to use seal of light (glyphed) as this spec.
The glyphs you have now are the ones I used to roll with, however, I had art of war instead of light's grace as well as a few other talents deeper in the ret tree. You'll want the instant flashes of light in PVP, trust me. The less you stop and cast, the more you will be able to LOS/kite, and the less vulnerable to interrupts you will be.
I think this is something along the lines of the spec I used to use, if anyone cares:
http://talent.mmo-champion.com/?pala...A42Z,6b8,10676