“if the community generally doesn’t do something, but it is permitted al pi halacha, that won’t stop me from doing it privately.”
You seem to be under the impression that an individual is not halachically bound by community custom and can privately disregard it if he / she sees fit. This is generally false. It is true in the the following scenarios:
1) When a custom varies from community to community AND the individual is a visitor who is privately acting in accordance with the custom of their home community (or a talmid keeping the practice of his rebbe).
2) When a custom is a boorish error
Neither of the above apply to our case since there are no communities where women had a custom to wear tzitzis and no Rabbonim who instructed that they ought to adopt such a practice. In fact the opposite is true, Rabbonim have objected to them doing so.
Also, I am aware that the Rema holds that if a woman puts on tzitzis she would make a bracha. This is in line with The Rema’s psak (and Ashkenazik custom) that women make a bracha on time bound mitzvot as opposed to the Shulchan Aruch’s psak that they do not. This has no bearing on the fact that women did not in practice wear tzitzis, a practice which the Rema considered a show of arrogance. You should also be aware that the Levush holds (based on Targum Yerushami) that a woman who wears tzitsis transgresses the Torah prohibition of wearing male garments.
“I am pretty much done with this topic, so if you rebut anything here, I will let you have the last word.”
Ok, will do