So im thinking if i should regem and gear more crit then haste. At the moment, UNBUFFED, I am at 24.01% holy crit, 387 MP5, 549 haste(16.74%=1.3 cast time flash heal). In all my raids, the only heals that i cast are flash heal and a little bit of PoH with serendipity at 3 stacks. With crit, I can easily get more surge of light which will increase my healing done and cause me to go OOM slower. With haste, I am planing to get haste so that my flash heal is 1.2 cast time, but I want to do it all at once. So im wondering would crit be better to gear/gem for and just leave my haste as it is with flash heals 1.3 cast time?
Step 1: Stop using over-using Flash Heal.
Step 2: Start using Renew more.
Step 3: Gear for more haste. Minimum of ~655.
Step 4: Don't be afraid to cast PoH without Serendipity up.
Step 5: ???
Step 6: Profit?
Seriously, read the stickies, read the talent discussion, read the other posts on the forum about this same exact topic. Haste is superior to Crit. You've tricked yourself into favoring Crit because of poor play-style choices.
Haste still reduces the GCD for instant spells, which makes it useful to gem for. That doesn't mean that you should gem for straight haste or stack haste, but it should be somewhere in your gemming scene. Priest gems are generally very diverse, spell power, spirit, haste, intellect, all good choices; just avoid crit.