For those interest in designing great puzzle games, I would suggest reading the following thesis on evaluating fun in puzzle games.

https://www.researchgate.net/publication/27476077_Automatic_...

(update: Non paywalled version https://pdfs.semanticscholar.org/e401/51cbec7bdcc65b59fff53c...)

Cameron Browne (the author), suggest many way to evaluate your puzzle, and this was used in his further research as a way to automatically generate fun and interesting puzzle games.

http://cambolbro.com/games/index.html