In 2008, the IIHF published a European League ranking to be used for seeding for the now-defunct Champions Hockey League.
Apparently, this ranking was based on judging the strength of the best club teams in each league, as well as the overall strength of leagues (sportive parity and depth, infrastructure, economic stability, market dimension etc.). The sportive criteria that had been taken into consideration were primarily the results in the European Champions Cup (2005-2008) and the last three years’ participation in the Continental Cup.
The 2008 IIHF League Ranking for CHL seeding.
1. Russia
2. Finland
3. Czech Republic
4. Sweden
5. Slovakia
6. Switzerland
7. Germany
8. Belarus
9. Latvia
10. Denmark
11. Austria
12. Kazakhstan
13. Norway
14. France
15. Slovenia
16. Italy
17. Hungary
18. Poland
19. Netherlands
20. Ukraine
21. Great Britain
22. Romania
23. Lithuania
24. Croatia
25. Serbia
26. Estonia
27. Bulgaria
28. Spain
29. Turkey
30. Israel
Now, one can make many arguments against the order displayed above (for instance, it baffles me to see us Dutchies ranked above Ukraine and Great-Britain. Even though the EIHL is highly overrated, they shouldn't be ranked THAT low).
Then again, that was 2008, and it's 2012 now. I'd say that the Swiss NLA is definitely the top European league behind the KHL. After that, ranking becomes more difficult. I'd say that Sweden & Finland round out the top 4. There has been a serious talent drain from both the Czech & Slovak leagues, so I wouldn't rank the Extraligas that high anymore.
Latvia shouldn't be ranked that high either. They have great talent and a great team with Dynamo Riga, but their own domestic league isn't of that high a standard.
Same goes for Denmark. Since a lot of the teams ran into financial troubles a few years ago, the league is rebuilding, but hasn't reached the same level yet.
If one goes further down the list: Serbia doens't even HAVE a domestic league anymore, so they shouldn't even be on this list. They do have one decent team (Partizan Belgrado) playing in the Slovenian league.
All this being said, we still haven't added the North-America minor pro leagues into this mix. As well as some second tier leagues (Allsvenskan, Mestis, VHL, 2. Bundesliga, etc.) that would easily rank within the top 20. And we mustn't forget the Asian Hockey League either. Those teams operate with budgets that many European teams can only dream about.