Fwiw...the assumption is that when you sketch a revision that you are working on the latest one. Again another assumption is that you add a new revision when one starts...not adding ten at the start of the project. If you follow these assumptions then the next revision cloud you get is assigned to the "correct" revision...no extra work so to speak. Regardless the Options Bar makes short work or reassigning a cloud. Whether you make a selection first or second...same result, Tomayto...Tomahto...
Sooo the current system steps are:
1. Create new revision - Settings menu > Revisions
2. Draw new revision cloud - it's assigned to this new revision...no extra work.
3. Tag it
Again this assumes that you are not dealing with a multitude of revisions at once...you finished the previous revision earlier...now you are starting another. Making assumptions/decisions are the key to software and programming. Writing software ain't for the faint of heart....