You wouldn't get 5 years to noodle -- maybe 1 or 2 at best. You're competing for your next thing against other smart folks who are going hard on maximizing publication rate and grant winning in their current thing. To continue with your riskier, bigger thinking you'd have to be ready to bet that: (i) you'll produce a highly impactful result before you start applying for your next thing and (ii) the high impactfulness of that result will be recognized in time to support your applications.

The most successful folks tend to mix talent and hard work with a bit of luck in terms of early gold striking to gain a quick boost of credibility that helps them draw other people into their fold (eg, grad students in a big lab) who can handle a lot of the metric maxxing to free up some (still not enough) time for more ambitious thinking.