This is a deliberately vanilla core set not a detail one, so the rating is base on how good this set does its job not whether it could be "prettier." This set does a good job of representing the basic dungeon tiles. Corridors: straight, 90 degree turn, T-intersection, 4-way intersection, stairs straight, stairs 90 degree turn and several dead ends into small rooms. Rooms: corners, sides, with entrance and non-entrance versions; middle sections and L-wing connectors. Everything you need to build a basic dungeon and all worth 5 stars so far for this type of set.
So why take off a star for this set? There are no doors. Not one. This set has to be viewed as a replacement to the old E-Adventure Tiles Dungeons Volume 1 (SKG105e) which had a door and non-door version of every room entry and had doors on some of the passage intersections as well. Honestly, there were probably too many door tiles in the original set - but to go from lots to none takes off a lot of this set's utility.
I don't think this set needs a lot of doors/non-door variant tiles like were in the original set, but I would like to see a page added to the set that just had doors you could cut out and place on the other tiles: a varity of 5' x 10' sections with a 5 foot wide door, a pair of 5 foot wide doors, a single 10 foot wide door and so on. It would be nice if larger double doors could be included that were like 5' x 15' and 5' x 20'.