Going from a G10 to a 6D... Am I dumb?

Provided you take the time to learn photography, a full frame camera can be a nice investment. Access to various lenses can be nice, but you will still probably want your own lens so you might want to figure that into the budget. And I would always rather have better glass and cheaper cameras than better cameras with cheeper glass. To start, I might imagine that the Canon 24-105 f/4 would be a great all purpose lens on a 6D. We use the Nikon 24-120 on a D600 probably 80% of the time.