Those of us who have traditionally worked on snes9x4p have done 'drive by' porting. (I kicked off the port, and then Ivanovic and others have taken over, so blame us

-- we made it work on Pandora, customizing it, changing the menu items, adding nice screen filters and scaling .. but this is all superficial dressings; the actual core work is the snes9x team of course, and then in turn SiEnCe for dingoo and such did a lot of hacking around to pick and choose features and so forth. So most of the work is snes9x team (and this version is not following any core work there at all), and SiEnCe's work (which does continue along, but not in large leaps.)
So what would be needed is someone to take an interest who actually is a passionate SNES person.
I barely touched a SNES in my life .. I did the port for others, and hence left it at a point when it was 'good enough'; then Ivanovic and sebt3 and others took over to make it to their level of 'good enough'; but none of us are hardcore SNES heads, and hence our various definitions of 'good enough' might not be enough
Raise the flag and stir it up, maybe you can find a dev with some time who will adopt it.
There is also the option to do a fresh port of current snes9x project; we did it a couple years ago and ran into some oddities, but maybe those are addressed by now (seems likely given the many ARM devices out there), so maybe a fresh snes9x port would have more features and accuracy (and is very easy to do, sans a GUI). I recall doing a fresh build of current snes9x only took half an hour to pull off, to see if it worked.
jeff