It's all a process. You can use ZS with MF as I do, typically we get into an area and shoot at least a roll therefore your roll will
be consistent when processed. True, ZS is not needed but you need to know your camera and how it meters. The photo looks great by
the way. Sometimes I will simply find an area in the scene I want to be a nuetral gray(zone 5/6), then everything falls into place, sometimes
I expose for the shadow and develop for hilites. Depends what you want the outcome to be. Proper use of spotmeter and ZS when doing
large format is almost always required, sheet film is more expensive and you can't afford to bracket 3-4 shots. As suggested get a grey card
and a grey scale find out how your camera meters and your spotmeter go from there. Or do as you do, seems to work. Everyones
sugestions are good, find what works for you and refine it.

"Opinion is the medium between knowledge and ignorance."