That should be fairly achievable with either-macs.
I started out with Aquamacs, but ended up getting annoyed with enough of the differences that I finally switched back to the (then Carbon, now Cocoa) emacs.
Most of the useful settings live in the ns- customize-variable land.
; open all new files in existing frame
(setq ns-pop-up-frames nil)
; make Cmd act as meta.
(setq ns-command-modifier 'meta)
; ... C-h v ns- TAB TAB