Harry wouldn’t leave Chicago, his family are there his friends are there and Demonreach is there. His trapdoor is there. He loves that trapdoor. More importantly Mab wants him there. He is there at Christmas Eve. More likely he would move a lot of Warden operations to Chicago, it is a much bigger transport hub than Edinburgh, meaning it has more connections with the Never Never allowing for better Warden deployment and the three largest problems in the last few decades have been the Red Court based in South America, the heirs of Kemmler (Chicago) and the Titan attack (also Chicago). Edinburgh not so much unless you count the problems building the tram system. If Luccio is tapped for the Senior Council it would be a little awkward for her to work day in and out with Harry (the sorry tale of workplace romances) so a bit of distance may be order.
Now if only Harry had access to a large fortified building with wards equivalent to Edinburgh in which to work out of with residential facilities, a gym, a boardroom for meetings and a large hall for operations/ training/ function space, he could work from home, a lot of people are doing it now and it is time to drag the White Council kicking and screaming into the world of 20th century employment practices.......hmmmm.
It would also help if Harry had an isolated but secure baby Warden training facility, call it Camp Spooky which doubled up as a supermax prison where he could set up a juvenile wing for young warlocks instead of executing them which as a former young warlock is something he strongly dissapproves of and handily can now practically end.....hmmmmmm.
His use of Demonreach will be widely known after Battle Ground, the Senior Council will have to recognise that he is The Warden, definitive article, not a Warden. The Wardens are named after The Warden, and I suspect Captain of Wardens exists as post when there is no Warden (definitive article). For all we know Warden was a Senior Council post like Merlin, or GateKeeper which lapsed when no one was stupid enough to claim Demonreach as a sanctum. Then along came Harry. Chandler is a historian, he would know (now isn’t that handy that we just found that out, and he is for once in Chicago)
I would point out that there is a large amount of super warded stone on Demonreach in the ruined lighthouse, only a quarter of which was used to build the cottage, Harry can use the remainder for either building on his castle, or for building something like a bunkhouse for trainees on Demonreach itself, just need Alfred to block wardens from the Islands influence, which Harry has handily realised Alfred can probably do. This would be handy as there are increasing numbers of Wizards in need of training.
I think Harry is going to realise that he has through his choices and circumstance painted himself into a corner with the White Council and not the one he thought he had, instead of being pushed out, he is going to be pushed much further in.
