Welps... If I had to pick for a console, the most recent thing that comes to mind is the overall architecture in Metroid Prime, the first one. That game was just so well done and put together.

For most hated level, I'd have to say the Super Mario World (SNES) star map 2? I think it was... The one where you have to keep eating the balloons to float through the entire level. HATE. Pure, raw, unabating, hatred.