The simple v. easy section was interesting. Those words are probably used too often as synonyms. In reality, we should think of them differently - something easy is something that a lot of people should be able to replicate without much expertise, whereas something simple, a lot of people should be able to understand (what it does, the purpose, how to use what was built), but not necessarily replicate themselves. I think that is probably the right distinction, although it is a very fine one.