Malkorok is the obvious one, Dark Shamans(melee group), Nazgrim, Immerseus, Sha of Pride with the strat your raid is running, Paragons if your tanks need more healing.
I use Vuhdo, which is inbuilt into the addon. Grid does it as well, but you need to download a separate modifier for that.
That means your guild isn't splitting up the healers efficiently. Find a spot where lesser healers are assigned and heal said areas.
SH is more about the sustained shielding over the burst shielding, so it's really up to you in this case.
You got your answer, then.
From what I know/IIRC, Aladya hates SH, and he has given good reasons for doing so, so I doubt he's running SH. There are no haste breakpoints for SH, just run as much as you can without dropping mastery.
SH is pretty bad for Immerseus, really. EF is so much stronger for topping up puddles.
For protectors, you are hitting so many casts of LoD while EF is slotted.
For Sha, you are running SH with that silly 4-way split strat. Good luck trying to hit the right targets with LoD.
P.S. Your pally partner suffers from similar pitfalls. Both you and Holypung need to ask yourselves whether SH or EF is more suitable for the specific strat your guild is running.