"Look, this is no different than "Trinity" icons depicting God the Father as a very old man, or "Old Man Time" icons depicting Father/Christ as a very old man, that are allowed to subsist in Orthodox churches."
I suppose not, heretical practices like doing metanias at the mere mention of Panagia and using pictures of the Trinity or Christ with old men in them are inappropriate. That the priest did not instruct the old lady is a shame but you and I both know that that was his call. As for the Trinity pictures, well, I'd like to see a couple of them gone from my parish but I was the only "old timer" to want that, so I commissioned, from a Syrianitsa, a Holy Trinity icon which is prominent in the narthex of our church. There's not much else I can do at least for now. I do not believe, however, that chanting "Υπεραγια Θεοτοκε, σοσον ημας", knowing full well what we are talking about, is heretical. Kosta mou, I have been, like you, chanting that all my life and it never occurred to me that I was, or would be thought to be, asking her to do for me what Christ does until a convert asked me about it a few years ago.
I think your level of catechisis and theological understanding is not the level of an average parishioner, Kolo mou.
PS BTW, the vocative case ending in Slavonic for "Υπεραγια Θεοτοκε" is also "e" (Пресветая Богородице). I wonder if that is by coincidence or by design.