Gregor, looks like you are making good progress on all the accessories, so your procrastination on the tower has clearly been put to good use..;-). On the tower interior, if it was me, I would cobble up a "generic" interior based of of the plans and pictures, to fit the doors and windows on the tower. Eg WX office, lav, duty office and ready room on the ground floor. Radio, flight control, and somebody's office on the 1st floor, then radios, WX instruments and binoculars in the observation room on the roof. Or something like that.
And since I'm forever coming across wrong on the 'net, Gregor I'm not criticizing your work or ideas, I'm just offering up some thoughts on how I'd address building the interior that might be useful to you.
Rick