I'm in my 40s too, and I'm not going for incubators or accelerators. I can't afford to as I burned all my saved capital last year, taking 6 months away from contracting to build my product. I've got a mortgage to pay and a family to support, so I've got to work a day job while bootstrapping in the evenings and weekends. If you can afford to not have a day job for the three (?) months of the YC program, then more power to you. I'm sure you'll benefit from their network and expertise.