Hi,
There is an image for the pi zero here that I think works with Pi 3 B, I’m sure I used it on mine. kingosticks has mentioned there is a new version imminent once he has his Pi Zero W.
Not sure about the soundcard, I use a usb soundcard on Pi Zero after some trial and error it now works fine- best to get set up and try it, I only use the headphone socket on the Pi 3
There is a touchscreen info here I prefer to use either the browser or remote control.