I came across this website; it has several articles that cover the different nuances of level design.
http://renegadesector.com/level-design-primer/
Develop games in your browser. Powerful, performant & highly capable.
Interesting, have you read the book "Game Design: Secrets of the Sages"? You can buy a used one on Amazon for $0.01! (plus $3.99 shipping) That's a great deal!