Good points.
The thing about Las Vegas in winter is that it will so seldom get below 40 on a mornings commute that its not worth tooling up for anything less. I can drive 3 days in the winter when it does get colder. The same thinking holds true for rain. I expect a real commuter would not shy away from either but when it seldom happens it may not be worth considering.
I probably have answered my own question. Right now I'm thinking nylon long handles under mountain bike shorts and light fleece under ultralight wind breaker. Maybe a do rag under my helmet and my REI ultralight daypack to bring this stuff home at night.
I was really wondering if you guys knew of any technical ultralight clothes especially suited for bicycling or designed specifically for bicycling.
I really don't want any luggage on this bike as I plan on putting a touring bike together in the spring.