yes. in your first 2 proposals, you’re asking for some extra layer(s) of complexity whose benefits i just can’t see outweighing the costs. just educating folks that, at some level, obscured observations exist and that they may show up in nonintuitive ways on the map is a much simpler and effective solution, though no solution is going to be perfect.
of your proposals, i think the least objectionable is the last one:
… but i think a better version of this request would be to allow the user to select which map style – grid, pins, heatmap – they prefer to see, regardless of zoom level.
the cons vary depending on the exactly how you implement any particular change. i could write many, many paragraphs to explain exactly what all the problems are for each approach, but there are too many potential implementations, and for simplicity, i’m just going to say that it mostly boils down to unnecessary complexity. you’re effectively asking for the grid version of the map to gain extra options that other versions of the map – like the pins – don’t. you’re asking potentially for a new type of map visualization to be created, too, and to be mixed together with the grid version of the map. so that’s extra processing power and maintenance, too.
someone asked for something similar to charlie’s first proposal a while back: https://forum.inaturalist.org/t/option-to-display-obscuration-rectangles-grid-on-explore-map/7646. the reasoning for the change in that thread was a little different than the reasoning in this thread, and in that thread, i describe mostly why it’s a bad approach from the perspective of privacy, since that was the main con in in the context of that thread, while unnecessary complexity is the main con in the context of this thread (and in general).