There is an entire tower in the Underdark with an absent landlord that you only see the pieces of what they were doing there and his dangerous infernal machines left running an empty tower. I thought I had discovered everything in that tower but apparently I missed like 5 things!
I friggin love that tower! So cool. I also really enjoy finding interesting places like this, and bits of lore in the game. There's so much, and so much more being hinted at that we haven't seen yet. It is far, far too early to pass judgment or to limit ourselves in play style. Just try EVERYTHING!