Stop posting. Not everyone hates this game as much as you do. Instead of crying about how much you think everyone should quit this game in EVERY single thread u create / visit. Just quit it urself already. And f*** off from the forums ur a plague.
Well what most good pvpers do play with is the Standard Ui, without any help from any addons.
Using Grid and all those addons i would not recommend for pvp. I don't even know what most of them do but i guess its like click heal.
You should make several Dispel macros for certain party members (decursive will be too slow) Same for shields and everything else you'd want to do without having to target ur party members. Also bind targeting Party members to something easy to reach.
And as a disc priest, try to not cast much, use mostly shields PoM penance and renew for healing. Only casting spells like Greater heal Flash heal etc when it's really needed. Like in ur Inner focus. and often then 1 is enough cus it will most likely crit.