The top European leagues are pretty equal to each other, but if the Russians can keep paying the kind of salaries they currently are, the RSL will soon become clearly the second best of all hockey leagues. It's hard to compare the AHL and the European leagues because the style of game is so different, but the top players of the AHL are usually also top players in Europe and vice versa. The goalies are better in the AHL than in any of the European leagues, players are generally bigger and tougher, but less skilled than in Europe.
SM-liiga isn't the second/third best anymore, so many star players have left Finland in recent years. In the Swiss league, the best players are pretty much equal with any other top league, but the depth isn't there yet.
My ranking:
1. NHL
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2. RSL
- - - - - - - -
3. AHL
4. Elitserien
5. SM-liiga
6. Extraliga
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7. Swiss A-league
8. DEL (Germany)
The ranking of course depends on whether you want to compare just the level of players or include level of coaching, organizations in general etc. into the equation.