[Kaimetsu]

It's pretty much impossible to identity a 'best' developer in any field other than scripting. Style is an important factor. Spanky puts lots of detail into his levels, and some people like that. Personally, I don't. I prefer grand architecture and easy of exploration to crowded minutia, but I recognise that everybody's entitled to their own standards.

What I like to see in levels is interactivity. NPCs that respond to your presence, or simply objects that the player can manipulate. Most people treat level making like it's just painting a picture, ignoring the fact that a person has to walk around in their creation.