It looks like the DailyMail was a little premature. Jane Goldman (X-Men First Class, Stardust) has spoken out the rumor that her next writing project is Kick-Ass 2 via Twitter.
"Saw a few erroneous reports today that I’m currently writing Kick Ass 2 script – sorry if anyone’s disappointed, but not true. Currently writing for 2 other projects, then on to lovely Matthew V’s next thing (right now, looks unlikely to be KA2) when X-Men post-prod’ ends."
While she doesn't mention the possible projects they very well could be comic book related. TheGuardian mentioned that Jonathan Ross was hopeful his prohibition era vampire gangster comic Turf could be made into a film by Vaughn. Ross is a famous comedian in the UK and it doesn't hurt that his wife is Goldman. The project seems different enough that it could be very appealing to both Goldman and Vaughn. I could see it ending up a mix between Boardwalk Empire meets the original Blade film.
LatinoReview reported a few months back that Bloodshot was a project that Matthew and Jane were working on together with intentions of making it into a film. It was later stated by Mark Millar that they had turned it down but it's unknown if Millar is reliable anymore. Speaking of Millar's reliability the comic book writer had stated that a big announcement concerning a live-action adaption of his comic Superior which was to be made this month. It would reveal the film's director and possible lead actor. Millar previously tweeted that he gave Vaughn a first pass at the film.
"I've promised Matthew Vaughn a first pass at Superior though. We're going to talk next week whether it's this, KA2 or something else next."