Managed to find my last road eventually. Was a TINY bit (like a millimetre) of grey on one of the dotted dirt tracks. All showcases done, all festivals upgraded, all exhibitions done, all xp and fast travel boards smashed, all barnfinds done.
I've got about 90% of the championships to do, all of the drift challenges (I haven't even done 1 as I hate them), and there are a few speed traps and jumps that I need to 3 star but I just can't seem to do them and they are now testing my patience.
I think the only thing I'll come back for now is to finish the championships and even then I don't really think I can be bothered as I've already done all the races as exhibitions.
Is there any DLC coming out for this game in the future? Wondering whether to keep hold of it or not. I remember the Burnout Paradise DLC expansion and that was absolutely brilliant. If they bring something like that out with a whole new area I'll think I'll keep hold of it...