In an alternate Batman Begins, we have:
Jake Gyllenhaal as Bruce Wayne/Batman
Daniel Day-Lewis/Viggo Mortensen/Russell Crowe as Ducard/Ra's
Anthony Hopkins as Alfred
Chris Cooper as Gordon
Natalie Portman, Rachel McAdams, or Emily Blunt as Rachel (they were interested, but Nolan wanted Holmes)
Ewan McGregor or Christopher Eccleston as Dr. Crane/Scarecrow
and Laurence Fishburne as Lucius Fox
Personally I think I prefer Caine over Hopkins or Alfred, and I definitely prefer Christian Bale and Cillian Murphy, but Cooper as Gordon and Fishburne as Fox could have been interesting, though I'm fine with Oldman and Freeman.
Also Colin Farrell's role in the Total Recall remake and Dominic Cooper's role in Abraham Lincoln: Vampire Hunter were almost Tom Hardy, but he was busy for TR and I think turned down AL: VH.
Jake Gyllenhaal was almost Ledger's role in The Patriot with Mel Gibson, and almost replaced Tobey Maguire in Spider-Man 2 because Maguire hurt his back filming Seabiscuit.
Nicole Kidman was cast in Panic Room, but had to leave when she fell down the stairs and hurt herself, and Jodie Foster stepped in.