I think you can analyse this too much. There are no definitive answers, unfortunately, for those in the age dilemma. It's a risk - and the older you are, the greater the risk - that only you can decide whether you're willing to take.
If you have no external commitments, that does make it easier. If you do have those commitments, you really, really have to think this through very carefully, and you must never embark on anything without ensuring that those who depend on you totally understand the risks and fully support you (financially if necessary). If you're not sure that your family can take that risk, then there's no question; this course of action is not for you. The consequences of failure are too high.
Scroggs