1-Trees. tunnels are nice, but open holes with a line of trees or trees surrounding the basket works too.
2-Good signage; the worst thing is to go to a new course and have no clue where to go. i like to see the distance too. i don't care if the sign doesnt have a 'map' of the hole, as long as it says how far it is and where the next hole is.
3-a course where there aren't ten people in one group....they never let you pass....
4-concrete tees; i'm fine with dirt tees, too, i guess.
5-not alot of water. it's an obstacle if the designers work it into the course well enough, but man, i lost my favorite disc in the middle of a large pond...
that's about it. i don't care about elevation, benches, cleanliness, or any of that. if it's a challenging course, i'll have fun with it.