There are a number of relatively advanced military aircraft on the market now and it would be nice to have access to some of the data specific to those operations. I understand your data source is civil in nature but much is applicable to civil aircraft (TACAN DME can be used by civil aircraft, etc) This is also a fairly US centric request since much of that data is publicly available.
- TACAN data – this is already in the nav data but missing elements such as Channel number that some sim avionics need.
- Military Training Routes - these are charted on civil charts, but having access to display them, select them, flight plan then, and view their makeup (waypoints, etc) would be amazing. This detailed data is also publicly available: https://www.daip.jcs.mil/pdf/ap1b.pdf and MTR Segment
There may be other data but much is locked behind DOD access controls. These mentioned are available now and have civil aircraft implications/usability in addition to military.