Sadly, iPhone and the iPod Nano 7G don't work in quite that way, you can't just run SU and install it into /sys/bin/, Apple had put many more things in to prevent jailbreaks. Although if Apple devices were easier to jailbreak, and jailbreak developers were allowed even MORE development options, more useful tools would come out for Cydia. In the end, Apple would get more sales, but that's just not how Apple works...Hey fella's so I've just stumbled upon this and figure I'd give it a shot. I have a 7th gen Nano and would like to fully customize it in the manners similar to rooting an android. I've had some experience with customROM work on the android and I've also had experience with customization on iPhone3 (via jail break, then became more advanced). Lastly, I've worked with firmware and lpwl files (sorry if I have those letters out of place) for customization and firmware modding when limewire was a huge thing.
I'll let you know what I find.