Also when I was interviewing friends who have solar about their systems, one thing that kept coming up when I asked them "what they would do differently if they could do it all over again," was to have a clear plan, and the space required for adding more panels in the future. They all did the calculations and thought they were going to have plenty excess, but usage patterns change, people put on additions, get new hobbies, buy bigger appliances now that the energy is "free," etc. and almost everyone I know has added to their system.
And about the "green" thing, all technology needs early adopters, and yes the carbon footprint is still high, but in the end it is encouraging innovation in renewable energy sources. We can't sit idly by and just wait for non-renewable resources to run out. Just in our own system the advancement from our old panels that are 10 years old to the new ones we added last year is fantastic. Panels now are at least half the cost, half the size, and put out double the amount of energy.