I'm Mooh's age (46), and like him I play fingerstyle and with a flatpick. I don't think either is inherently more limiting than the other; they're just different approaches. Martin Simpson is an incredible fingerpicker, and Tony Rice is an incredible flatpicker. Who's better? I don't know; it's a silly question, really.

If you want to achieve maximum versatility, do both. If you started with one, and are wondering when is the best time to try the other? That's easy -- right now.