It would be nice if webmin had a module allowing you to easily manage, edit, and create SELinux policies.
Agreed. It's on the todo list. (Unfortunately, SELinux has the worst configuration process on the planet. It's downright baroque. Leave it to the government to build something so elaborate...Even POSIX ACLs are simpler.)
We'll probably need libselinux bindings for Perl to get it right, which don't exist yet, so we'll have to write them ourselves (which is a pretty huge project in and of itself), though we might punt in the short term and just call the appropriate command line utilities (which'll work just fine, but be a bit slower and less flexible than having the full libselinux interface).