This is a well-written article that gives a good understanding of the game.

I also love your attitude over board games:

Good table gaming should be an interactive, intellectual, social and pleasant exchange

Often times, we get to caught up with the "mission" to win that the game becomes too though. Hence, it destroys rather than build friendship.

I also play Splendor, and I wasn't aware that there is an expansion until I came across this post. Thanks!