Alfonso Cuaron or Matthew Vaughn would be my two favorites to Direct the next Bond film.
The next Bond film needs to be Directed by a SOLID, experienced Director and not some inexperienced and unproven Director that the Broccolis love rolling the dice with from time to time and end up crapping out.
When have the producers ever done that? With the possible exception of Peter Hunt and John Glen (who were promoted after proving themselves in other roles), the director's chosen have always been experienced - if this was intended as some dig at Mark Forster it's way off because 1)he was widely experienced before taking on QOS and 2)he's got a much stronger/exstensive track record than Matthew Vaughn who you suggested above.
Well lets see....who directed The World is Not Enough, Tomorrow Never Dies, Die Another Day? Then we had Forsters one dimensional and unbalanced QOS.
Campbell has easily been the best overall director the Bond films have had the last 10-15 years! Granted it can also be attributed to script and story, but GoldenEye and Casino Royale have been the two best Bond films overall the last 10-15 years IMO.
Time to get some REAL good directors like Alfonso Cuaron and bring a fun yet complex Bond story that will executed differently than any previous Bond film....since Campbell won't be returning anytime soon.