people need to keep in mind that because there are only 2 sets, there probably wont be bonuses that affect disc/holy spells specifically. i.e. no CoH or penance or maybe even pws but probably not pwb(barrier). I like the haste idea with inner fire, but its probably too much because inner fire is a passive buff and 5%haste would become mandatory. People are right that the only useful shadow ones would be in increasing damage, but knowing blizzard, mana efficiency and odd tricks will probably win out.
PoM and GH are used by both specs, and while they seem to be better used in the holy tree, i see disc priests casting pom too. I would like to see something done with flash heal in the 2-piece because both specs reliably use it, but refreshing renew might not be the best course because renew has a relatively shot duration, especially with the glyph, and trying to refresh it on people that are already healed, because renew can be effectively used to raid heal, might not be great. Cast times and haste seem to be the trick, but there is still room to increase crit when certain abilities are active.
I wish they made two sets for both disc and holy, because things like grace, divine aegis, and holy concentration need some bonus love all by themselves. 5%mana on GH was a waste cause it ends up being somehting like 50 mana to a holy priest. The extra jump for PoM was nice on a few fights where it mattered, but aside from Saph and Maly, who needs 7 jumps when recasting on the tank will probably happen sooner.