I couldn't help but notice you lack a nifty feature another format had, and it seems possible to implement here.
The feature was [acronym][/acronym] this feature allowed not only acronyms to be defined but allowed for the use of unknown languages in roleplays while allowing the reader to understand what it meant while the character didn't for example: [acronym=live long and prosper]Vilo pelm oot pokwet[/acronym]
How it worked: the word(s) in particular would have a dotted underline drawing the interest of the reader, hovering over the word would cause a text box to appear showing what it meant.
Note, this didn't work for mobile
I don't expect this for core, but for an add-on yes