Of course, a full length parallel taxiway at BNA would help with the traffic, even if only part of it was for GA (<5700kg). Let's see the Council work on that as part of the fix.
As for a tower, Airservices I think has a couple of portable towers the likes of which have been seen at MNG and PF. A little bit of effort and one could be at BNA by Xmas.
But to get there we have to endure the internal politics of both CASA and ASA, so don't hold your breath!