Is it possible to add another hotkey to use the offset that gives the best throughput, for machines and containers? It's more complicated for belts, undergrounds and splitters. Double-tapping alt-F might also work.

Adjusting all 3 settings for best throughput would be even better, but probably more complicated, since it needs to know not only what entity is on the tile, but all the tiles covered by the entity.

I've already got a note reading

some setting to automatically pick the fastest estimated drop offset when drop offset selection gets skipped through any means

I'm unsure if it's better to have a separate key bind, a setting, or both of those options.
I've also added a note now to automatically pick the fastest estimated combination of pickup and drop positions, probably through a different key bind.

There's several key binds that should be added to the mod, specifically for all the "power users" out there who prerfer pressing 1 button that does multiple things rather than going through the whole configuration process of inserters every time. Unfortunately I've not had the motivation to extract all of the offset adjustment logic out to be able to be used without the in world UI. Not that it would be particularly hard, I just didn't feel like it so far. So all I can say for now is that I've taken note of this so if I come back to it at some point I won't forget about it.

Three keys in sequence might work, moving your finger one key to the ?left? for each step. Lots of options.

It's still an amazing useful mod. Seeing the speed as I move the mouse is much better than trial and error, going in and out of the GUI each time.