That seems like a lot of work. If what you want is to be able to run MacOS X apps on a free (like in free speech) environment, there's https://www.darlinghq.org/ which is like Wine but for MacOs X apps.
If what you want is to replicate the MacOS X UI you can customize the UI of your DE on Linux, or use something like ElementaryOS or use Pantheon.
I find this gtk application theme and shell theme to go even further than elementary. The developer releases all sorts of themes with insane quality. You can even tweak them to suit your preference such as sidebar width and compact header size
I admit that I haven't personally used Darling but it would be rather pointless if it only worked for commander line apps. All command line apps I use on MacOs X are from homebrew and are available in Linux so for me it only makes sense for GUI apps. Also, I never really missed a MacOs X specific app when I use Linux, most apps I use are multi platform anyway, and the rare one that is not, it usually has a decent equivalent for Linux.
If what you want is to replicate the MacOS X UI you can customize the UI of your DE on Linux, or use something like ElementaryOS or use Pantheon.
What are the goals of this project?