Any sim game recommendations that fit your criteria?
Furthermore, the performance hit when upgrading to higher resolutions is negligible. Smaller pixel densities require heavy supersampling to look good whereas higher density displays can be run at or near their native resolution.
I got the rift in order to play it only to realize that learning DCS from the ground up requires a lot of keyboard input / referencing cheat sheets so need to be pretty proficient with it before you can't see your hands and as you mentioned the resolution is not quite good enough in rift to really see things with much detail though it is still a fun experience to try out.
Looking forward to playing it on a future headset.