Keep in mind that very few people make it through a PhD program with a good enough outcome to become a professor, and it usually has less to do with intelligence, than with luck, social skills, and the ability to "play the game". And if you do manage to get a faculty position (somewhere...), you've got another six years of hard work ahead of you before you've got any true claim on autonomy. Then you get paid dirt for the rest of your life.
You can always go to grad school later, but you've only got so many years of youthful enthusiasm and the ability to live cheaply. And once you have a wife and kid(s), it gets a lot harder to start a company. My advice is to take the massive-upside risks when you're young, and leave the low-upside risks for later.
Keep in mind that very few people make it through a PhD program with a good enough outcome to become a professor, and it usually has less to do with intelligence, than with luck, social skills, and the ability to "play the game". And if you do manage to get a faculty position (somewhere...), you've got another six years of hard work ahead of you before you've got any true claim on autonomy. Then you get paid dirt for the rest of your life.
You can always go to grad school later, but you've only got so many years of youthful enthusiasm and the ability to live cheaply. And once you have a wife and kid(s), it gets a lot harder to start a company. My advice is to take the massive-upside risks when you're young, and leave the low-upside risks for later.