I applaud the work you have done so far, Apollon0011. Back in the FSX days, I really liked flying old aircraft to custom mid-1900s airports using modified navaids representative of that time.
I wish that MSFS would incorporate the concept of eras into the sim. It would make what you and other community & 3rd-party developers are doing so much easier. If MS/AS added an “eras” tag to the metadata of an object - be that scenery, aircraft, navaids, etc. etc. - which specified an enable start date & disable end date - and provided an option in the MSFS GUI for users to choose a time period to fly in, then one could fly entirely in the present or any time period in the past. There would have to also have to be a conflict resolution process put in place to decide which object was displayed in cases where the eras metadata overlapped.
I look forward to seeing your progress is this endeavor! 
Edit: FYI, there is a wishlist related to this topic: Historic airports, aircraft, flights, eras etc for MSFS