You have a LOT of options here:
probably the one that will be the least work to get 80% of the possible functionality would be to just prepend
/Applications/Emacs.app/Contents/MacOS/ to your
PATH variable (in your
.bash_profile if you don't want to do this manually all the time; I'm assuming you use bash) and invoke the program as Emacs, that way you get the cli behavior you expect when launching emacs, and the gui for the actual editing (to skip the gui use the -nx flag when starting emacs); and then you can also
alias emacs=Emacs so you don't have to get the case right or change your habits.
another option is to start an emacs daemon (
/Applications/Emacs.app/Contents/MacOS/Emacs --daemon) and pass it files with emacsclient which you can just alias to emacs like
alias emacs="emacsclient -t -s $TMPDIR/emacs$(id -u)/server"; in addition to this there's the option of starting the daemon from launchd when you login, in case your emacs is slow to start.