Unless there will be only one train, a signalling system will be required, and that cannot be specified without knowing the stock to be used.
All plans show two tracks all the way just like LGW and talk about state of the art technology. I can only see a single track used at quiet times overnight when maintenance takes place.
As far as advertising, we have had EZY sponsoring the LGW shuttle for years, now replaced by BA, perhaps they will be back at LTN being painted Orange!