If one unintentionally evacuates a plane, it continues on its merry path whilst the player plummets to their (potential) death.

That's fair.

Though what is a little annoying is finding said plane after the event. Although the one in question was indeed recovered (by chance), would it be reasonable to add a GPS tracker as one of the plane upgrades?

I'm not sure how that would work with vanilla, but there are various map mods that show entities as icons on the map. Perhaps that could be used? Or maybe a new item that showed the direction of the vehicle being tracked...

Wouldn't a compass do the trick ? Like the lodestone one, although I'm not sure if it can work since the plane is an entity