Our workflow involves always putting a change request id in the commit message. If we want to cherry-pick a change request which involved multiple commits, I go to the search view in SourceTree, search for the commits, copy the SHA-1 code, go to the log view, jump to the SHA-1, then cherry pick.
It would be a lot nicer if I could search for the change request in the search view, then mulit-select the matching commits and cherry-pick.