Hey Fridge, haven’t you learned that using VR is more art than science 
?
Good news - I don’t think that you need either a hardware upgrade or a rebuild. You don’t mention what CPU you are using, but I’m running an AMD R5 5600X on Windows 11 and it’s not having any noticeable impact. Your 6800 XT rates slightly higher than my 3080 in the latest Tom’s Hardware Benchmarks.
Most games seem to benefit from using an upscaler in VR and there is a pretty easy to use interface for both the AMD tech, FSR, and the Nvidia tech, NIS. @fearlessfrog has created a great post for this. Once installed, with some minor tweaking, it runs automatically when the sim loads, but can be toggled on/off and or tweaked on the fly if needed. YMMV, but in general, it seems to add 10 to 20 fps in DCS with some sharpening. I think that the X-Plane dudes are using this. Worth a read through.
If you have returned from the dark side, MSFS uses OpenXR as the Mixed Reality runtime instead of SteamVR like everyone else. There have been good results using an upscaler with it called OpenXR Toolkit. Great intro video here.
