They're pretty cool! Those other adventure maps mentioned at the top of that link, The Legend of Zelda - Two Worlds and Echoes of the Lost World are awesome, even without the new wiring stuff... though some of the jumps requiring a frustrating amount of skill and timing.

I'd give them a try, as well.

You'll find geyser traps are generated near the underworld. However, if you play the Tales of the Terrarian map, there are some in that map you can scavenge after you complete the world, by going back in with a pick. >_>

(For as much time as I've logged in the game, I don't have much in the way of amazing architecture to show for it. I tend to build very functional boxes for my stuff. ^_^ I still have my first world and, though my main base is a tower that stretches all the way from the top to the bottom of the world -just a long box-, my original base is still there, and still very much a large Hobbit hole.)