EDIT: Or the zeiss 18mm! It's not too big, and close to my ideal focal length, thoughts on these two lenses?Well, the weight there might be getting away from your "light" classification, but, if you're at the 18mm Zeiss, consider the 21mm as well (even heavier though). Every review I've read says its the best lens in that focal length range.
Voigtlander weighs about a 1/3rd of the Zeiss lenses...
Yeah, the Voigt is looking like the one to check out ... funny I never knew about that brand.