Support with Impossible Goal

I am working on setting an impossible goal. I recently quit my job and am taking time off. I have been a workaholic for over a decade. Work is where all my extra time went. Thus I never took time to develop personal interests. I would like to set my goal as: Identify a hobby that fulfills me and that I am regularly doing and improving in. I think this would be a playful goal which would be good for me. But is this measurable enough?