About X-Forwarded-Proto, We could release a prop that enables the additional headers. The prop can be enabled by default starting from 7.10. I’d avoid a new UI checkbox because the new default behavior shouldn’t harm in 98% of cases 
RequestHeader set "X-Forwarded-Proto" expr=%{REQUEST_SCHEME}
RequestHeader set "X-Forwarded-SSL" expr=%{HTTPS}
Current template:
Also X-Forwarded-For, X-Forwarded-Host and Forwarded are interesting 
https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Forwarded