Ok so whats next?

[Letum]

Originally Posted by FC99

That's my main concern. Is it worth it to do it if there might be a handful of people who will use it in the end.

It might be an idea to see if you can find some mission makers to start making missions for several branched campaigns so some can be released along side the branched campaign patch. If you struggle to find any one to make missions before you start work on a branched campaign mechanic, then it probably won't add much value to the game.