Oh, I've finished every inch of Clouds long ago, except for four places that need lost keys and Dragon Cave. I've explored a pretty big chunk of Darkside as well. I've done:
A2-A4
B1-B4
C1-C4
D1-D4
E1-E4
Castleview
Castleview Sewer
Ellinger's Tower
Troll Holes
Gemstone Mines
Escape Pod 2
Sandcaster
Sandcaster Sewer
Northern Tower