When I think of "rock and goth", I just think of rock music with horror themes. Is that supposed to be like Kiss or Marilyn Manson? MJ was never a proper rock musician, but he had some elements of the genre in songs such as "Beat It", "Dirty Diana", "Give in to Me", "D.S.", "Morphine", "Shout", "We've Had Enough", "Privacy", etc. If that was the sort of music he was working on in his final years, then that's fine, but I don't think he was working with the right producers for that.
I read before that some of the songs MJ did were will.i.am were completed? One of them was called "The Future". I doubt they were good, but I'd actually be interested in hearing them someday; I'm guessing they were the only songs that MJ recorded and completed from 2006-2009? Pretty scummy that will.i.am refused to release for the Michael and Xscape albums, but wanted to put them out for his own album in 2013, btw.
I'd love to hear more of the stuff he made with Brad Buxer. I like "I Am the Loser", which was recorded in 2003, before it was slightly reworked into "I Was the Loser" in 2008. Although it was never completed, I also liked "Days in Gloucestershire"; it was recorded in 2004 and you can tell it was made at a difficult period in MJ's life.