A couple of flaws to mention, because I'm too lazy to review the pack in full. Keep in mind that I stopped playing at Drowned Downtown zone because I hated the level so much:
-Needs moar texture variation. Too many levels have only one or two textures plastered on every wall.
-Please fix the skies in your levels. The first level's sky is waaay to high up, the second doesn't fit, and the third is even worse.
-Too much darkness! Your caves are way too dark. Many times I'd get lost or fall into pits because everything is so damned dark. Software + Darkness hurts the eyes.
-Drowned Downtown.
This level applies to most everything above and then some. The level design is bland. Boring. It's almost excusable in Act 1 because it wasn't that long, but Act 2 really took it's place in my list of one of the worst levels I've ever played. After ~5 minutes of playing (and with the taste of act 1 still in my mouth), everything just blended into a bland mesh of the same brick textures, dark colormap, and boring mazelike design. There's nothing redeeming here, no interesting set pieces, the map is downright ugly, and the only thing that isn't completely forgettable is how damn long it took me. Perhaps I'm just being biased, as I hate underwater levels/gargoyle puzzles and you just happened to put me through both at the same time, but I honestly didn't enjoy this at all. Throw in some more textures, some more interesting design, and don't make everything so dark. Make some cool sector-based lighting effects or something if you have to, anything to make the level more interesting. Until then I don't plan on playing this level ever again.