I stopped reading at '"real" Emacs is typically installed via Homebrew at /usr/local/bin/emacs'.
You can download and install 24.5-1 at http://emacsformacosx.com/ without having to use homebrew.
GNU Emacs 24.5.1 (x86_64-apple-darwin14.3.0, NS apple-appkit-1347.57) of 2015-04-13 on mymachine
Running this with Spacemacs is... well, surprisingly pleasant. Unicode, pixel level scrolling, image support that isn't totally broken, it's...nice.
What is the difference between that and brew install emacs --cocoa?