I shoot a Sony DSLR too and I think that the older Minolta lenses have been pretty good gems at reasonable prices (albeit, some too heavy, such as the metal 70-200 F-4 "beer can"). But since it's not a relative to your situation, I'll continue...

My brother has a NEX-7 so I'd like to see what you think about the Zeiss 28mm if you get your hands on one. I personally agree with the post above where a good wide angle will have to be under 20mm due to the non-FF crop factor. I have a very nice, sharp, fixed 50mm and I NEVER use it because it's simply too narrow of a field everywhere I go. You'll use it for portraits of others sitting in a chair and for nothing else. That's the only thing I've found it useful for. The 35mm sounds decent for portraits and for most other uses.

I have a 28-75 F2.8 all-purpose lens which I really like and would recommend. I don't know if they sell that for the Nex-7. If you're satisfied with the OEM lens, then my next lens would be a <20 mm zoom lens (fixed if it's somewhere in the 13-15 range). It's going to be a heck of a lot more useful than a 70-200 telephoto or a 50mm.