so, ive finished fully exploring the two existing sites. ive never gone to so much trouble to get a single adamantium mace, whoever that was. tremendous fun exploring. that inaccessible fort i complained about earlier did have a stupidly obvious entrance i missed somehow, along with a deviously well hidden back door.
the end of my heroic adventurer occurded in an interesting way - pulling a lever, thinking "oh that did nothing" then walking forwards a few paces and having a set of adamantium floodgates (which i had spotted) close behind me, leaving the lever i pulled to activate them BEHIND me on the other side. i knew about the whole delay thing that happens with floodgates, but i never factored it into the turn based movement that happens in adventure mode. so aparently trapped i ended up drowning trying to explore water filled areas for a way out. note to everyone - don't kick down mysterious doors.
anyways, not to be on your case or anything Boski, but im dying to play the next fort that comes out. mucking around in someone elses built area was much more fun then i thought it was going to be, especially the "oh @%$#" moment when i realized i had irrevocably closed the way back, walling my companions off behind me.
something which i would find more fun would be more of a lived in feel. the two built areas present didnt have accessible living and communal spaces. Toady does try to make his world feel alive, so making places that feel lived in or functional in some way would be more interesting. even the pyramids have nearby ruins of the workers quarters.
the other thing is, don't be too clever. puzzles that involve throwing switches then marching across the map to see if something has happened are not fun, at least, not for me. If things are going to be ludicrously well hidden, then write a cryptic text file or something that can masquerade as an old peice of paper your adventurer starts with, and send it on with the save. if your doing tricky water puzzles it may be a good idea to do adequate drainage with floor grates and underground spaces absolutely everywhere it is possible for someone to accidentally flood.
last thing - that brook that dropped into a giant canyon was crazy awesome. it went nearly to the bottom of the map and changed to "muddy brook" in its description. i didn't know the game had natural features like that, though you can only see it in adventure mode if you jump off the edge.