This is probably a long shot and would presumably require a plugin, but I would love to have options for different sets of tags.
Basically my process is this: I have #tags for topics, but to link notes back to texts they reference, I use ∑authoryear. This isn’t an official tag so there’s no autofill or searchable list. Previously I’d been linking them to a lit note for that text, but this clutters the graph in ways I don’t want.
(There are other conceivable ways around this–being able to exclude the folder where I keep my lit notes from the graph would be one, and there are others too–but this would be a nice option.)