I plan to do this repeatedly for future nano builds and written a series of scripts for this purpose.
I did this for 2 reasons:
1. I like working with nano and want it on my RaspberryPi on Ubuntu Core
2. I think nano is a great text editor and others should also benefit from using nano on Ubuntu Core + Raspberry.
If you ever consider packing nano build for armhf as a snap pleas let me know.