It's fun to read lists like these , but we don't know if these movies still were so succesful with different actors.
I don't think anyone could have been better than Sharon Stone as Catherine Tramell in Basic Instinct.
Or Tom Hanks in Forrest Gump.
Or Harrison Ford in Indiana Jones.
But I agree, Hugh would have been a much better Billy Flynn.
And Phantom in The Phantom of the Opera.
But he did not turn down the last one , he wasn't aviable.