I posted the following thread at the SAS 1946 website, which is a large modding community for the original IL-2 Sturmovik 1946 classic series of 2nd World War flight simulators and modifications, particularly the SAS ModAct and BAT.
For head tracking, it is possible to use opentrack with Valve SteamVR as input protocol and freetrack as output. Just remember to disable the vorpX head tracking.
No matter what, on my WMR I am always a bit cross-eyed and head tracking is stuttery. The Valve SteamVR translated to freetrack and sent to the game is OK for rotation but does not work well for position.
Other than that – yes, it is a good fun nonetheless.