I don't see a need to change lisp. It does everything I've ever tried to do.
The biggest breakthrough was Common Lisp.
I don't quite understand your Emacs question. The biggest limiting factor of any lisp programming is me. Lisp is clay for the mind and sometimes my mind-clay is too dry. Lisp and Emacs don't limit me in any way.
That said, other languages "get in the way" all the time. It is nearly impossible to think of certain ideas[0] . Try merging your rule based expert system approach with your subsumption based knowledge representation system so that rules and knowledge are two surface representations of the same (lisp) structure[1].
I have no comment about Wolfram software.
[0] The Sapir-Whorf hypothesis states that the grammatical and more verbal structure of a person's language influences how they perceive the world. It emphasizes that language either determines or influences one's thoughts.
[1] Integrating rules and inheritance networks in a knowledge-based financial marketing consultation system https://www.computer.org/csdl/proceedings-article/hicss/1988...)