On modern browsers, I imagine it's possible to implement an htsp client using Javascript. That would allow you to do everything that Kodi can do, but would not allow any of the advanced config that the existing UI allows.
I'm not convinced we need anything embedded in the server (callbacks are a pain due to the python GIL). That's not to say an embedded language wouldn't be useful for advanced user configuration, such as generating filenames, or taking actions when files are deleted or finished recording.
But many might be better off just using edit4ever!'s tvh2kodi that runs inside Kodi to do the tvh configuration. It offers a nice menu based system, where you just go 1,2,3,4,5 and then everything is mapped, scanned, and working.