I think Jaws of the Lion broke the rules down for Gloomhaven really well -- it introduced the complexities of the game slowly over scenarios. I would advise anyone who has a game that takes more than a couple of hours to play to have a way to start the game and then add complexity after initial barriers have been met.

Mechs vs. Minions is another one that does this iterative process of teaching.

This article looks great, I'll continue to read it.