RTH waypoints could be an option? Rather easy to implement.
One awesome feature of full-scale glass cockpit systems these days is Synthetic Vision. I've been hoping this works it's way into FPV OSD's in the distant future. It's not too overly complicated either. Just pull terrain mapping data and overlay. Could be implemented in the ground station software to start.
Don't listen to me though, I'm a full-scale IFR pilot who is used to 60k avionic suites
I've actually mapped out an IFR-like approach at my field using waypoints. When the wx is right I'm planning on flying FPV IFR approaches!
For now though I'd love to be able to change the overlay color of the OSD to green, but I know that may be a HW limitation.