Cipher Strength can certainly be improved upon via web server configuration. I imagine the same for LiteSpeed and NGINX when it's released.
Key Exchange is specifically to do with the Let's Encrypt certificate, so I believe Enhance would need to change it from 2048 to 4096 bits internally.
Right now though, we can't actually modify the vHost config in any web server, can we? I would like that option in future especially with NGINX. I currently have NGINX configs where requests to /foo/ are proxied either to external or internal ports as because I can't edit even the Apache configs (probably can do via .htaccess though), I can migrate them into ECP.