labeling – Improving label collisions for Tree/Graph?

Historically, MMA has never handled label collisions well, but recently they added some improvements here via things like Callout. I want to fix ImageSize but still see as much as possible (by tooltipping a minimally set of vertices).

Here’s two examples of the problem:

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Unfortunately, Callout doesn’t work in Graphics but it does on ListPlot type functions… any ideas?