For example, moving to Horspath (next to the training ground area) or Sandy Lane would see us having to reduce the capacity significantly & cause a significant strain on road infrastructure.
Building on a rugby pitch near Bicester Village is moving the club out of the 'city' although probably high up on the well researched* list of options no doubt - I'm sure it has benefits to the new board.
Water Eaton - things move on I'm sure but can't see it.
Moving to Wycombe or Northampton in a hissy fit to try and get one up on a landlord is suicidal. Actually an idiotic suggestion.
Meanwhile, staying at the Kassam Stadium, finding a deal that suits all, building a fourth stand (YES FK said he'd do that), filling in corners, getting Colin B's architects back to a table**, sat next to a new train station hub linking the city centre, seeing thousands of houses being built on the SODC side of Grenoble Road, a community hub for a growing part of the city suburbs - doesn't sound a bad idea, does it?
*research probably extends to speaking to people at Sunderland, people at the EFL or looking through this very forum.
** club official quickly adds this to list of research and might actually speak to OXVOX who might be able to help