I'd like to have seen George Lazenby remain as James Bond in Diamonds are Forever and through the Moore era. He could have played a vengeful 007 hunting down Blofeld in DAF and would have been still relatively young had he remained in the role until the mid-1980s.
George Lazenby was misled by a terrible agent who felt the Bond franchise was dying (but to be fair it was in bad shape when a surprisingly old looking Sean Connery starred in a relatively low rent looking Diamonds Are Forever
Robin Hood: Prince of Thieves with an actor who could sound English. Maybe Mel Gibson, if no actual Brit was available?
Actually Kevin Costner wanted to speak with a British accent, but for some reason the director and producers vetoed it.
A Bryan Singer-directed X-Men 3.
Things started going wrong with the X-Men
movie franchise when he slunk off to direct the somewhat underwhelming (from what I've heard) Superman Returns
. But The Last Stand
was still better than the utterly abominable Wolverine
(which had some of the worse CGI for a big budget movie ever, that looked as cheap and shoddy as the SFX used in the last two 1980s Superman