You got the right forum for the question, thanks for sharing your feedback. 
As far as I'm aware, Cupertino is just an alternate layout that makes use of a dock instead of a bottom panel for apps, it isn't strictly designed to be a OS X "lookalike", although I do agree with your suggestions that it could be.
But, with MATE you can customize an awful lot yourself quite easily:
- Remove the "Applications.. Places.. System" menu bar with "Main Menu".
- Add the global menu applet to the top panel.
- Change the window buttons to the left. The option is in MATE Tweak → Windows tab → "Window control placement"
- Change the icon and themes if you like. Here's one from the community: