With mazes you don't want the path to be too obvious. The player isn't going to walk down a corridor if they see that it's a dead end. Unless they are looking for a trap door or something. This goes for placing treasure chests. The player can see a chest on the other side of the wall but shouldn't see the path to get to it. Paths should be long enough that the player won't know if there is a turn or a dead end just off screen. Tip
: Scale the editor window down so that you only see as much of the map as you would in-game.
Man-made structures have straight lines. Mines, dungeons, and roads can be linear and straight forward. Nature is non-linear so there shouldn't be just one path. Combining both linear and non-linear areas keeps things interesting. An example would be a sewer system that's predictable and easy to navigate but the exits are barred; luckily there are a couple holes in the wall leads to a network of cave tunnels. The tunnels could take you outside or to parts of the sewer that you couldn't reach before that had treasure or an optional Alligator boss. Tip
:To make interior maps more explore-able, draw the hallways and rooms on different maps. This way the player won't walk past all the empty rooms and go straight to the armory or treasure chamber.http://www.skipmore.com/freegames/fairune/fairune.html
Play Fairune and pay attention to the areas with pillars. They break up the map up visually so you don't see the direct path or the next exit because you have to walk behind them. Then again at the temple, you see the switch inside but you need to go in through a different door. You go outside and see pillars where the door should be! If your paying attention you'll notice there is just enough space to walk behind the pillars and find the hidden door. Skipmore games are actually very short but are deceptive enough to keep you playing for a while.