Have you thought about following the life of a logistic bot?

Short answer: Yes :)

Longer answer: There are a lot of little issues that would need to be resolved to make logistic/construction bot targets viable for trainsaver, the main one being that I would want to ignore robots with a very short distance to their destination, and I don't currently know of any way to figure out what their target or path is.
For the moment trainsaver can target trains and spidertrons, and I am tentatively working on adding biter attack groups in the (hopefully near) future as well. Robots are on the "if possible, would be nice to have" potential target list :)

Yeah that would be cool, especially in stages of the game where trains are not yet researched, it would be cool to have a 'screensaver' mode where the game is just panning across the factory or observable map to keep screenburn from happening :)