I cant speak for PvE too much here, but for PvP losing AG really sucks for the dps specs of Shaman, especially Enhance but ele too just less than enhance.
Shamans only have a few defensive CDs, and they are on pretty long CDs. Earth Ele is 5 mins, Astral Wall is 2 min baseline, 1.5 min with talent (which means we can’t get stronger wall if we want short wall), Stone Bulwark is 3 mins. In PvP you can grab Burrow which is 2 mins, but it takes an honor talent slot which sucks. Compare that to any other class or spec, its quite bad.
Losing AG as a CD to rotate between these is definitely felt. With how high damage is in PvP, people eat through the initial shield of Stone Bulwark almost immediately (one slicing winds deletes it for example). You still take damage with Burrow if you have dots/bleeds on you, and the only semi short cd we have is wall (if short wall talented) but people can kill through a 40% DR now. AG allowed us to hold off on sending wall/stone bulwark immediately which felt pretty good, not the case anymore though.
It would be nice to see some slight improvements to spells that we already have. Maybe have Earth Shield grant 5% physical damage reduction to the Shaman? (can be buffed/nerfed in pve and on a spec by spec basis), maybe have Earth Ele grant a shield to the Shaman when its summoned? Maybe bake in short wall baseline so we can opt into strong wall if we want to improve wall at all? Maybe a choice node with Elemental Resistance that makes Healing Stream do a burst of healing to x amount of players when its dropped? Just something here would be nice.