4 Levels. Really, really well thought out. These would be really tough as net levels (unless you turned aliens off), but for practice, you won't find a better set. (In fact, these benefit from the Canyonlands textureset, but don't require it. )
Desert Levels. Great textures (first water I've seen outside of the M2 preview), and enough baddies that these levels work equally well as solo (explore) levels and net (kill) levels. The patch affects different texture sets than Bob World Headquarters (see above), so they can both be applied to the same Shapes file. This is now Rev 1, with a few textures fixed.
A cityscape, complete with great signage and some funky extras. By the same guy as Canyon Lands. These two packages patch different texture sets, so you can apply the patches to the same Shapes file.
