One of the ideas the Spectrum Next project has given me is making a PMOD connector for the Pi Zero.
I don't know if there's a protocol or anything for PMOD, or even how you'd access the PMOD boards (I'm assuming the MEGA65 guys have an idea for this considering they are adding the connectors to the official mainboard), but it could be pretty neat solution to adding WiFi (if you use a Zero W) as well as a co-processor and extra RAM etc.
I'm a bit sad really. My Nexys4 board is still pretty much in the box, and whilst I've had a bit of time to play recently, none of my monitors support the resolution of the MEGA65 :-(
I hope the "downgrade" to 1080p happens