I have 70 lvl shaman, mostly raided as enhancement but have alot of experience as resto

Ye its nice idea to use earthbind totem but on other hand it: a) can easy be destroyed b) there is curse of exhaustion (spelling) c) there is fear after all

chain heal is nice but there is a chance it will just to another players you dont want to heal and also it is only 3 targets. When you get heavy AoEd you need to do 5 targets heal, and fast

about dispeling. So what are you gonna do if one of your toons get sheeped? wait 10 sec on one place? thats isnt that good
and poison cleansing totem isnt godly against rogues because it can fail dispeling rogues' poisons so you have to wait another tick... so anyways you more likely will have to remove poison by yourself

about tremor, it does not remove those effects right away after landing. Tested 1000 times in pvp and pve. It can start pulsing whenever it wants withing 5 seconds.

imo shaman isnt perfect aoe healer. Yes shaman is insane solo healer, especially in pvp. I remember those funny moments when I was self healing alone against like 4-5 players and survived long enough untill reinforcements come AND smash them all.

also shaman is tough in case of melee but it becomes not that strong against spellcasters

pvp specced priest has alot of awesome features as well, the % of crit on you heals you, +20% to resist any interrupt mechanics after getting a crit, "shieldwall" etc etc etc