La Citta is one of those games where if you make a non-optimal move early then you'll spend the rest of the game in a downward spiral you won't recover from. Same with Acquire.
On your Knizia list I like Through The Desert and Ra. The rest I can live without playing again.
Fucking Reef Encounter is one of my top ten games. I'm a huge T&E fan also. Which one I like better tends to be the one I've played more recently. The two games play nothing alike though and RE isn't nearly as complex as it seems.
Lost Valley is worth getting if its a decent price. With three players I always force the river to go sideways so there's really only one side of it worth being on. Otherwise you can get one player on his own never interacting with anyone.
I'd throw Mermaid Rain into the pile. I like it about a zillion times more than I liked Elfenlandgold.
And in terms of Knizias I think Taj Mahal beats out Ra for my top spot. Great game, nothing else plays like it. Plenty interactive too (let me win the elephants damn it!)
I also like Reef Encounter a lot, although I never play it and don't know if I can remember how to play from the rulebook, which is awful.
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