My idea is like this
issue:
current shaman class mechanic
proposal
if you are casting damaging spells, you have a 5% chance to proc your current class mechanic for damaging spells only for 5 seconds, and same goes vise versa for healing spells.
summary
spamming damage -> 5% proc damage waaagh -> 5sec activate
spamming healing ->5% proc healing waaagh ->5sec activate
in my opinion that way it wont be abused, and the mechanic can be useful now

What do you guys think.
Thanks.