×Entrance - This was a nice opening room. It wasn't overly difficult, but definitely required patience.

1E - I discovered very recently that although easy to complete when you know what to do, this room is quite misleading in some ways, which was clever, but a little annoying.

2E - I liked this room, since it required a very clever manipulation of the queens and their offspring in order to get them out.

3E - This room, similar to 2E, also required a very interesting tactic to complete. It did, however, rely on monster movement order a bit too much, I think. If it was flipped horizontally, for example, the room would not be solvable.

1N 2E - The procedure required in this room was also clever. Being patient here was quite a necessity.

1N 3E - This room also required patience, but was quite easier than most of the other rooms. It resembles, strangely, a room from another hold, although I can't think where I've seen it before.

1N 4E - I agree with Eytan, although to a lesser degree. This was a very cool room with a clever solution, although the only difficult bit was just before hitting the orb (in the solution procedure).

2N 4E - This was another room that I enjoyed quite a lot. Manipulating the monsters required to complete the room was tricky.

2N 5E - This room is actually quite a bit easier than is apparent, although the roach queens needed to be moved in specific ways in order to complete the room.

2N 6E - The effect in this room was very cool, although the shape of the central section does give the solution away a bit.

2N 7E - Once you get the opening moves correct, this room also is a bit easier than it looks, since with a bit of route planning, the path isn't too difficult to find.