I have considerable experience with ss and still have two cars with the original ss paint. Back when I swore that "I'll always own black cars" (famous last words

) they were all single stage so for years it was basically all I had. IMO you just can't beat (high quality) single stage black! Sorta fragile stuff though.
While you do have to watch it with regard to UV exposure and other types of abuse, I agree with the carnauba recommendation.
Note that "feeding the paint" isn't always BS with single stage the way it is with basecoat/clear. SS can and will dry out if you neglect it (and it'll do it a little even if you *don't* neglect it). So products like the Meguiar's "pure polishes" (#3/#5/#7/#81/Deep Crystal #2), AKA "glazes" can be very beneficial.
Here's what I'd do:
Polish out the marring to your satisfaction remembering that black ss is about as soft as paint gets and that it's only original once (so I'd rather have imperfect thick paint than perfect paint that's been polished to the point of being very thin). If it's a repant be especially careful as it can be hard to tell how much you have to work with. Go easy on the high points and around edges. Don't freak out over all the pigment transfer on the pads and towels. Use soft MFs so you don't reintroduce marring after you've polished.
Then apply one of the above-mentioned pure polishes/glazes. They "wet" the surface and hydrate the paint (again, this isn't BS in *this* case). The oils/etc. in them were designed for this exact application. With all but #5, buff off before completely dry. #5 can be buffed off wet or dry (the most idiot-proof product ever IMO). Be careful to use soft MFs and gentle techniques.
Then apply a good carnauba and either "layer" it with spit-shining type techniques or, at least, reapply quite frequently, say after most washes. Again, be very gentle so you don't mar the paint.
Topping with something like Souveran might give an added appearance boost, but I'd use something more durable for the initial waxing unless it's a garage queen.
#26 can look great on ss black (deep, rich, and dark) but the durability isn't stellar. I'd probably choose the wax based on the appearance/durability priorities. I would not use Gold Class, just not the look I like on this kind of paint. Black ss is one paint where the subtle differences between LSPs aren't always so subtle
