>>38
I'm >>7,10,18,34,37 (and a few others).
There are always tradeoffs to be made between doing something correctly and just getting it done. As I have said, I am against it both on principle and because of past experience with its flaws, but if people are so eager to get this thing made that they can't wait another couple months to see some text superimposed on a background image, then fine, go ahead and use Ren'Py and make a proof-of-concept. You could even use PowerPoint for all I care. Port it to an engine written in Scheme once you run up against the limitations inherent in the tools that are close at hand.
If people can have slightly more patience, but can't contribute enough effort to write it in Scheme, maybe Common Lisp is a better compromise. That Shinmera joker made a game with SBCL. I've had my eye on the dialogue engine for a couple months. It wouldn't be a bad starting point.