I'm in a similar breadwinner situation, but I'm not hanging on to the job for lack of an idea. I have tons of ideas, but I don't feel like I can commit the time required to make any of them succeed. 5-15 hours a week requires a dogged persistence over a long period of time. I might be able to focus on something for 6-12 months, but I think that working on something for several years with the slow progress that my time constraints would imply would drive me crazy.

I guess I'm still looking for the idea that drives me through the limitations.