Various researchers have tried to value draft picks based on various metrics. Below are a few interesting ones for GMs to consider as they manage their teams in the future.
No matter what metric you value it by, it's clear earlier picks are exponentially worth more, and values evens out in the later rounds.
Articles on Value of Draft Picks:
Based on time on ice http://theleafsnation.com/2011/3/16/on-relative-worth-of-draft-picks
Based on goals vs threshold http://www.puckprospectus.com/article.php?articleid=187
Based on games played http://myslu.stlawu.edu/~msch/sports/Schuckers_NHL_Draft.pdf
Based on actual NHL trade value http://www.broadstreethockey.com/2013/4/25/4262594/nhl-draft-pick-value-trading-up
Article on League Equivalencies:
This is another interesting article, as GMs compare draft picks from different leagues. Is the WHL better than the OHL better than the QMJHL? How does someone playing in SM-Liiga compare to the KHL?