Got it! thanks for the explanation Michael.
I see the logic, but seems a bit cumbersome for the filtering system.

> there will instead be a "Set filter" option
> on a pop-out menu and there would be
> a variety of options for setting the filter,

This sounds better, I'm picturing something like you tick or pick type (say curve) and the colour from the filter
and that's all that can be selected from the viewport, so you can either Ctrl+A or window the objects, is this
what you had in mind ?

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