I've always found minor keys easier to play in. I'm a cellist as well and I play in a quartet, for a while we were doing loads of Mozart in major keys and I said 'Cant we do something minor and depressing?' I always find it easier to let the music speak to me if its minor and emotional.

Plus if you have a nice guitar part in a minor key you can actually feel good about listening to it. The Smashing Pumpkins write some ****ing miserable lyrics but their music always awakens a good feeling inside me. I dont think thats the idea of their work, but everyones music affects people in different ways.