Just another input to think about. I have always wanted this but haven't checked recently on it. Maybe the database link can be standardized using a server client layer in between. Although it will require running of a sqlite server which I see is possible (for example
https://github.com/forchid/sqlite-server), the huge advantage that comes with it is then you can have tiddlywiki be served from a web server with any kind of database in the back. And then it can act as a personal wiki and store tiddlers just as it does right now and also be used as a shared wiki by marking tiddlers from a remote source.
In my opinion this would make it extremely useful and scalable to groups from a personal wiki level. Although it will bring new issues like permissions, conflicts and all, I think just having this first step would be a big step, and those issues can be resolved in small teams using other means if they want to use it.
Milind