Highlander is in itself a very self contained story. Conner becomes the One, there are no more immortals, and he loses his Immortality as part of the Prize. Of course the other Movies sucked, they had nothing left to work with. Lambert's age is not the only reason, in my mind, why Duncan was so Important to Highlander. THey needed to undo the first movie's ending, and to make that work you need a different Highlander as the star.
Of course that's just my opinion.
The Gathering: A Highlander Fan Guild
