Milestones to my mind is odd. It would be great just to have the aircraft housed by era, showing the progression of aviation technology from the early days of RFC then into the RAF and up to the modern age.
And painted up as a Fortress III the RAFM’s B-17 would look very different than the usual 8th AF yawn that B-17s usually end up as.

(source) That would be s simple conversion, right? And as a WWII type the B-17 is rather well represented so hopefully not so many howls of vandalism for adding that radome and arial?.
Then we could perhaps get the Liberator done up in Coastal Command decor?