If the bass power needs to be activated first then that changes the value of ebb/flow. The Failure will also be applied to allied characters checks unless you use the Magnitude upgrade... which reduces the number of Failures your applying.
So Disruptive Strike can provide a 1 for 1 return to a single target.
Ebb/Flow on the other hand can only provide 1 less than the Pips you spend, with a potential for 2 or more less to avoid impacting allies.
Disruptive strike hasn't lost its value IMHO.