Self was definitely an influence. It's where the prototype inheritance came from. Not sure that's a good thing. Smalltalk was more traditional in its inheritance model even if it was all duck typing.
For UI, prototype inheritance was nicer on the Newton (NewtonScript) than on the several of the class-based stuff I played with[1]. Morphic include in Pharo / Squeak is based on Self's UI. I actually like a prototype (other than performance issues) more than class-based. It has a much nicer, lighter feel for me. I just don't think Javascript is the best at it. I loved programming NewtonScript other than its clunky syntax in places. NeXTSTEP got around a lot of crappy class-based behavior by having live objects.
1) I swear I still have nightmares that include OnOk