Okay here goes. Original Westworld was pretty good, probably before it's time when it came out. Michael Crichton continues to impress me. That said, if the new version tried to stick to exactly the same story, it would have been a steaming pile of shit and HBO would never have touched it. Not because the original was bad, but because it didn't have enough depth for a series (can any 1.5 hour movie?), and it needed to be updated to speak to today's audience. I think a fitting analogy would be if you tried to make a modern day horror movie where every one has land lines and the bad guy cuts the power. Great for any time before the 2000's, laughable for any time after.
I really enjoyed seeing where the new writers pulled all the elements of the new show from. The feel of the updated basement and work area is right on, as is the guest's first introduction to the park, from the hover craft and trams, to the Blacksmith being one of the first buildings you see in the background. OBC, you mentioned the music in the new one. The end scene music of the original seems to be the backbone of the updated music. One of my favorite elements of the new is modern music disguised as old timey piano music and the time it takes me to identify the artist/song each episode. Memorable stuff from the new version is Nine Inch Nails and RadioHead.
Conclusion: The original was great for when it was released, but the new version is leagues better, and it has to be or else it'd be a flop. Pretty much all of the main story elements of the original are worked into the new version, but buried within an enormous level of depth. Tip of the hat to the writers for sure. Having seen both makes me appreciate both on a deeper level and I'm glad I spent the time to watch the original.