Gonna get this ball rolling with low hanging fruit… For me, personally, it’s gotta be Hokkaido in the reboot trilogy. My favorite aesthetics, I like how compact the level is and the way the outfits work.
Before the reboot trilogy it’d probably be heaven and hell in Blood Money.
Miami is definitely a legendary level. So many different areas and vibes and everything is done excellently. The race manipulation objectives are also very cool and put a highlight on the time loop style of the Hitman levels. Dartmoor is also very cool, but for very different reasons.