Rattle cans would do the job if you have lots of patience but I would avoid it on such a large panel.
What's a decent rattle can these days, £12? Say you use 6, that's £72 and that still won't give you enough material to polish back well.
Providing the roof is sound, I would suggest leaving the yellow or leaving the wrap and save up for a respray but obviously, it's up to you 
Have an ask around local bodyshops, You might be surprised at the price of painting just a roof black. It may not be as much as you expect
I’ve just been out to the garage and yeah the wrap looks awful so that’s coming straight off!
Turns out my girlfriend of 8 years has just told me she has a uncle who sprays cars and lives about 4 miles away... SHE COULD HAVE SAID SOONER!!!! Women....
Gonna contact him and have a chat.
I dunno if this is another one of my stupid questions but for little paint repair (where the bonnet safety hook hits the grill area I’ve been using Halfords rover primula paint. There’s a few bits I want to do but my local Halfords have no rover primula... the ford Daytona yellow looks the same to me would this be close enough for just a few touch ups ??