Unfortunately you are correct in that it is a bit early to say exactly how we will implement auto-relisting. It is still in the design phase.
It should be very customizable and able to do what you suggested though, such as relisting if the item sells, or doesnt sell, automatically increasing/decreasing the starting price when relisting, relisting for a certain number of times, and on certain days/times, etc.
But like I said I can't say anything for sure as of yet!
-- Auctiva David