You mention you are going to us the WP music for the Bradbury ending sequence. If you intend to make your edit as different as possible, it is of course ideal to put it in. The way I see it though, is that it is not music intended for Blade Runner and it doesn’t really work here.
Having said that, I do have to admit that I kinda like the alternate ‘tears in rain’ rooftop scene with the alternate narration and the John Williams score from the Workprint. The score that is used in the Bradbury-chase in the WP is however degrading the movie I think.
When watching the WP the other day with a friend of mine (who wasn’t familiar with the WP bootleg and isn’t a BR die-hard), he turned to me midway through the Bradbury chase asking 'what this 3rd rate horror movie music was doing here.' Well, that was rather roughly spoken, but I’m afraid I have to agree with him that is it out of place here.
I don’t know if there is a way to work around this music by keeping the alternate WP scenes in and use Vangelis score of the theatrical version, but I would love to hear your thoughts on this anyway and I look forward to your work….whatever way it turns out!!