I'm big on the Gould version, as noted above. He fit the time period. I didn't get driving the Cabriolet, and some of the non-stop smoking seems like some kind of forced joke, but all the other updates were fine with me.

I think there is a lot potential for a 21st century Marlowe. I'd give a guy like Bryan Cranston a shot at him. Mark Ruffalo might be a fit. Clooney maybe. Willem Defoe. I'd stay away from the pretty boys.

Bosch, to some degree, is a modern-day Marlowe, although he does actually work for the LAPD. I actually thought his pad overlooking LA was Gould's pad from The Long Goodbye. Some distinct similarities.