Level Design Patterns in 2D Games
I really enjoyed the Commander Keen series. But also Duke Nukem 1-2 (2D), Crystal Caves, Bio Menace. Or Game of Robot.I always found that some of the platformer games of consoles, like Super Mario, Donkey Kong, had much more simplistic and kind of boring levels. You did not had to collect keys to enter doors, or do other more complicated things, but basically it was mostly dexterity.This aspect comes a bit short in this article, I think. To me it was always kind of crucial, how much such puzzle element there was in the  game, whether I liked a platformer game or not.