I tend to look at the Director's Cut & the Theatrical Cut as two different versions of the same story. Little changes in the DC make a significant impact on how the film is read, and in my opinion makes 'Blade Runner' richer and gives me more to think about.
The TC is basically a straight up sci-fi action film, with some compelling ideas, but not quite as compelling as the DC.
At any rate, I'm glad that all of these different versions exist...