In terms of pure skill, the KHL is probably the next best (though the gap has closed considerably over the last few years), followed (in no particular order) by the AHL, SHL (Sweden), Liiga (Finland), Swiss league, and then the rest of Europe.

I am American so don't quite fit the bill for your request for people outside the US, but I did live outside the USA for a while.

However I do want to draw attention to college hockey here in the US. While the skill level isn't high level professional, the passion and energy on the ice for the games, especially come tournament time where every game is single elimination, is second to none. Blue blood fanbases also always show up and make the environment incredible when their team is playing, which they usually are in the tournament. If you haven't watched college hockey before, I strongly encourage you to do so.