Sounds solid -- good luck - thanks for posting back
TRY IT -- you have nothing to loose - it will cost you nothing except the non contact thermometer that you may [ or should ] have anyway
if the warm side bath gains too much energy or warmth - you can simply shield or insulate some of the radiation /baseboard [don't block the flow - block the radiation of energy into the room] with a rug or something creative that will pose no fire / trip / or other safety hazard - then keep balancing
BTW -- this isn't exactly the best time of season to test and correct because the outdoor temperatures do not give the load much of a challenge - so tweek slightly
or simply wait till next December and go for it
oh -- just one thing more - via that diagram you will be choking flow on the WRONG side of the circulator that is piped [ apparently ] to pump [sort of] at the point of no pressure change - don't let that blow you away - its just a simple way to support the advice from above - BUT don't choke too much and defiantly don't' choke both sides in of this diagram at the same time - if you have been reading you will immediately know why and this advice is redundant - just trying to help avoid a mistake.