The design is very flat and repetitive, it feels like the author didn't put much effort in both tiles and sprites placing. The levels themselves look like they've been edited from the originals, which is not good. The effort in finding secret exits wasn't extreme, but not challengy either; it would've been cool if the key/keyholes were a bit more hidden. Can't say much about the difficulty curve, since all the levels felt almost the same difficulty to me.
Aesthetic-wise, not much here. This is a vanilla hack, and thus, not much different stuff from the original has been used. Some cutoff here and there is present, and doesn't look much pleasant to see. An overall aesthetics that could've been better; probably you could've added more decorations so that levels could have been less empty.
- Music breaks on accurate emulators;
- While this hack tells you where to stop (aka after beating the 2nd castle) you can still keep going, since the original levels are still open.