Yep… a built-in benchmark scene like I remember seeing in some of the Gears of War games would be really nice. 
For my part, with 5800X3D, DDR4-3600 dual ranked RAM, and RTX 2070S, with render at 3440x1440 HDR and settings mixing High and Ultra bits: takeoff and landing at large airports (eg KLAX) with a lot of traffic (especially if using FSLTL on default settings) on never gives above 30fps.
It’s possible that some people out there might be getting much better performance in busy-airport scenarios without sacrificing a bunch of graphics settings, in which case I’d love to know their secret. 