One idea I've been toying wit (but don't have the skills to implement) is a standard for hardware that's a bit more verbose than things like i2c or serial. I'd like one connector I can plug into a piece of hardware (a sensor, a servo, a keypad, etc) and have it just work. The protocol would have to be a bit more complicated, maybe something like PJON^1, and you'd need to deliver power at a few different voltages.
I've been calling it kitbash in my head, just throw a bunch of components together in various topologies and you're good to go. Considering you can get a very cheap microcontroller for something like 40 cents I can definitely see the appeal of adding a "kitbash port" to various pieces of hardware, even if it means adding a whole new microcontroller.
1: https://github.com/gioblu/PJON