A software using CC-BY-NC-4 is not a good option, as it was made for media. If skiff markets itself as open source, it should respect the guidelines of opensource( it’s open source(https://opensource.org/osd/), you can read the 6th rule. It says the software should not be limited for commercial use.)
yes, it’s much needed now as many projects needs contributions and you can create a website and list all of the contributions that is required to make it a real foss alternative