This is a great all-round spec and I use it myself, would certainly recommend it.
Your gear is certainly ok, although not the best obviously. I'd say think hard about speccing out of Pursuit of Justice though. It's a contentious issue, but it gives you the edge in picking up mobs.
The survivabilty increase of Divinity is currently arguable due to the amount of overhealing done. With geared healers, it's simply not needed. Think about speccing into more threat as the scaling of dps with new gear starts to catch up with your threat.
Divine Guardian has great utility in many fights. I use this in main spec and improved Hammer of Justice in alt tank spec for fights like Faction champions. Imp HoJ is often overlooked but represents excellent damage mitigation in any fight where mobs are stunnable and interrupts where needed - Anub adds for instance.
Spiritual Attunement 2/2 isn't needed anywhere except Vezax or any fights which you vastly overgear. Very situational at best.
Seals of the Pure is ok for threat, but it's difficult to get there without losing Crusade (which is generally better for threat) or core tanking talents. If you vastly over gear content then go for it, but otherwise the linked spec with situational changes is a great all round spec.
That's all for now, 'kids'.
