Phil_Ozzy_Fer says:
Thank you for the suggestions Harrigan and Falcolnloft. I have some ideas already, but I'll definitely keep these in mind.
Conscious that you were looking for interested folks, then got a barrage of
maybe this, and this, and this! back. Sorry about that. I'd be interested in hearing more about what you have planned.
[ +- ] Clarification
(And to be clear, there are dozens of GMless games now, if not hundreds -- I was talking more about literally systemless freeform writing projects when I mentioned adding a simple dice mechanic.)