I doubt that you need the polyquat, given that you have the CYA and chlorine levels you report.
Polyquat is an effective clarifier, a persistent and moderately effective algaecide, and a weak sanitizer. I tend to view its primary value is providing a longer lasting algaecide during vacations OR for use in maintaining water quality when chlorine levels must be lowered, such as during stain removal. Other users may find benefits in other uses.
If you want to lower maintenance requirements during winter, I think raising borate levels to >60 ppm OR lowering phosphate levels to < 125 ppb might be something to look at. BUT . . . if you aren't having any algae or other problems as you are, and you don't need to 'abandon' the pool for a week or so during trips, I wouldn't try to fix what's not broken.
Does that answer your question?
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