Pretty much. I bought a 19 plate Sport Nav+ with the Safety Pack and looked into it all at the time. As you say, the only differences seem to be the colour of the leather and the scuff plates, which are an easy addition and do improve the look of the interior IMO.
The rear cross traffic alert/blind spot monitoring is incredibly useful, especially in an RF, and I emphatically agree that the Adaptive LED headlights are a revelation. My OH has a Mazda 6 with the Adaptive Front Lighting system and whilst it’s a novelty watching those swivel with the steering wheel the increase in available light with ALH in my RF is astonishing.
I think the GT at the time included the boot spoiler, but I’m not certain. The Sport Black did, which was based on the Sport Nav+ without the safety pack and only came in Eternal Blue Mica or another similar blue.
EDIT: I think the GT Sport Nav had BBS alloys as well, instead of the standard Mazda “Bright” alloys.