As an ex floor trader and derivative desk "guy",I can assure you that you will get that "6 th sense" that market makers develop if you stick with it ...you are way ahead of the curve
I do not make a big deal out of 1x3x2 vs 2x3x1 or any equivalent structure.What I do rely on is my ability to look at a screen and immediately pick up whether one strike/option is out of wack relative to the others..Your point was spot on,with the caveat we have to assume sticky strike vs sticky delta..
"or just looking N strikes/expirations up/down from the current one to roughly price a spot move/time change."
My only other "guess" is for these similar stuctures,you could price and/or compare them vs a flat skew,and compare the "Alpha" relationship,which I never do"_