My suggestion is that you make Rising World possible to buy and download independent of Steam. Barring that, create a code that allows one to run it without Steam. Taleworlds did this with the M&B series. I would not have purchased Warband otherwise. Also, a release to GOG would be suitable.
I have the original version of Rising World, but will not be buying the new version if it is a Steam required game.
Good luck with the new version.