it might be cool to build in a JSON editor with the game release, even the game itself, and to include modding instructions in the in game help menu.
the git stuff might be too much for that XD
I can see advantages to including an editor in the game package, in that it might be easier to keep up to date by using the same functions for interpereting JSON files as the base game does(lit. the same ones, not identical copies). That would keep the tool up to date
regardless of that, some well written and version-dated guides may be useful