Guile Scheme is a pretty nice language. It is a superset of r6rs and probably provides att bigger stdlib than ansi CL (with a proper module system with all the introspection you are used to from CL)
The reason for guile Emacs is that guile is the official extension language of the GNU project. It is a very capable implementation, and the elisp implementation is a lot cleaner than the one in Emacs.
You would also gain a lot of features not available in elisp. proper threading (with both pthreads and fibers, delimited continuations, and much more).
Not only that, you would get a runtime for elisp that works outside Emacs. Imagine being able to write programs and just load guile-org-mode and be able to script the org process without invoking Emacs.
The reason for guile Emacs is that guile is the official extension language of the GNU project. It is a very capable implementation, and the elisp implementation is a lot cleaner than the one in Emacs.
You would also gain a lot of features not available in elisp. proper threading (with both pthreads and fibers, delimited continuations, and much more).
Not only that, you would get a runtime for elisp that works outside Emacs. Imagine being able to write programs and just load guile-org-mode and be able to script the org process without invoking Emacs.