Yes. As a first step, improved JSON handling would help the ecosystem. That is, TiddlyWiki's "shallow" parsing of JSON structures needs improving, IMO.
Javascript isn't going anywhere (not for a long time, anyway). Everything that happens in TiddlyWiki is marshaled by/through Javascript. JSON (as Javascript's native data interchange format), is (should be) therefore, the "currency of choice" for any Javascript ecosystem. Indeed, just as it is in TiddlyWiki right now, but moreso.
How that might be exposed to the masses to get back what you're asking for, I'm really not sure. Maybe (maybe!) some JSON-defined ASTs, providing the mappings of terms-to-productions (yes, even regexes) would work?