Night fae or necro. Kyrian is a bit wonky for pve dps. Venthyr is in a similar state where its value for ele is particularly lacking and for enh its a bit of a meme aoe option that can’t quite edge out necrolord. Night fae and necro compete for best damage for enh and resto respectively while also having their own particular niches for resto. That being said shaman covenant abilities are all really good in their particular contexts, and I’d recommend mixing it up while you can.
As far a simple choice goes I’d probably go night fae just because its a solid choice for all 3 and soulshape is really useful this raid tier. I’d recommend trying kyrian for resto in m+ specifically at some point however since its just really good damage.