Yesterday had a bit of a shock when one of the new recruits was telling me about his gear and his stats. I have been running around with 5.6k spellpower and 2600 spi and trying for 12% haste, and he told me that he had read lots of forums and that regen doesn't matter much and it's all about spellpower. It annoyed me actually and I decided that I would look into the whole thing a bit more.
Cannot be Tamed had some nice tables about haste. I then realised I had too much haste for raid healing, so I might be able to undo some of my haste a bit. Haste not only reduces my GCD to 1s (which is not achievable atm - I think you need 5489/6403 haste rating (with 5%/without)) but makes my hots tick more, so more haste = more ticks. Haste break points were listed in his blog, and 1423 is a nice number for raid healing (with 5% buff), because with that I can get a 1 extra tick of Regrowth (5), as well as 2 extra ticks off LB (12) and 1 extra tick of Rejuvenation (5) and one extra tick of Wild growth (8). Looks like I might drop some haste.
But I realised that almost every healer seems to be walking around with 6.5k+ spell power, and it was only me who was gimped. So I swapped out all my spirit trinkets and wore only the spell power ones, regemmed a lot of prismatic slots to spell power and replaced all my green level gems with blue level ones. Now I feel a bit better with spell power sitting around 6.1k, just need a nicer ring and bracers.
I copied his spec to raid the other day, and gave it a try. I was 0/3/38 before and went to 8/2/31 dropping points in NS, swift rejuv and improved rejuv, and keeping Nature's bounty. I decided I didn't like that and it is hopeless for PVP, so I respecced and took the points out of Nature's bounty and put them back into the other 3. I think Moonglow really does make a difference with healing and I do try and cast Healing touch every time Nature's grace procs, since HT is now under 2secs with that.