I find the categories in Ontario to be really hard to work with, and I'd like to suggest some improvements:
First, I'd suggest that all the categories which currently fall under the "Ontario, Canada" category be moved to the "Ontario" category, the people listed in "Ontario, Canada" be categorised to their correct towns, cities, etc., and, once it's empty, that the "Ontario, Canada" category be deleted. Until that happens, we're going to have duplication between those two categories.
Second, I'd suggest that all the "City of..." and "Town of..." categories be replaced by simply the name of the city or town. Granted, the legal name of these places is probably always "City of Toronto" or "Town of Fort Erie", or whatever, but nobody ever says, "I live in the City of Toronto." They just say, "I live in Toronto." Having "City of..." and "Town of..." categories just confuses people when they go to add a category like "Toronto, Ontario" and have it come up red. (You know they're going to say, "Seriously? Are you trying to tell me that Toronto doesn't exist?" Granted, if they ask in G2G, somebody will probably look up the Ontario categories and tell them to use "City of Toronto(Modern), Ontario", but they're going to look at that, and conclude that, if that's the official category, then we're all whacked.)
That brings up another point: There are a ton of categories in Ontario that have messed up spacing. Either there's a space before the comma (where there shouldn't be one), or there's no space after the comma (where there should be one). In some cases, there are duplicate categories; one with correct spacing, and one with incorrect spacing. Just cleaning up that mess would be a full-time job for somebody. Preferably somebody who's nit-picky enough that they can catch all of the errors, and would be motivated to fix them.
I'd also like to get rid of all the "Modern" (and, presumably, there are some "(Ancient)" ones kicking around) categories. I'm assuming that some party or parties unknown put those in to distinguish between places before or after the different municipal amalgamations that seem to be Ontario's provincial sport. But in my opinion, as long as a place has the same name, it should be the same category. For one thing, Toronto has gobbled up so many suburbs over the years that it would require a pile of categories, like "Toronto (Really, really ancient)", "Toronto (Not quite that ancient, but still pretty ancient)", and so on. Plus, with having multiple categories for a place with the same name, you would end up having to apply multiple categories (for the same place, mind you) to the profile of somebody who never moved from the place they were born.
I wold also like to suggest, because of all those amalgamations, that every category have before and after links in it. For instance, in the Regional Municipality of Niagara, Ontario category, there should be a link saying something like, "For events in what is now the Regional Municipality of Niagara before January 1, 1970, see Welland County, Ontario.", and a reciprocal link in the Welland County category. Similarly, all the places that existed before and after July 1, 1867 should have reciprocal links between the Ontario versions to the Canada West versions, and the same for places which existed before and after February 10, 1841 for the Canada West and Upper Canada versions. etc.
I'd also like to suggest that we make up our minds whether to list towns and cities under their respective counties and regional municipalities, or loose in the Ontario category. Personally, I think nesting them under the counties and regional municipalities would be better, because it would shorten up the category list under Ontario and make it easier to find the things that are there (although still have the category names be, for example, "Toronto, Ontario", and nest them through the upward links on those categories, rather than, for instance, "Fort Erie, Welland County"). But as it is now, some towns are nested under their respective counties and regional municipalities, and some are listed directly under Ontario. I haven't actually noticed any cases where that has led to duplicate categories, but I wouldn't be surprised if there were.
If we can agree to a common set of standards, and then implement them, Ontario categories should be a lot easier to use. (And, well, it would make us look, you know, competent.)