It takes approximately 25 years to complete 1 focus tree without any experience bonuses or lifestyle events. While the Health bonus from Whole of Body is substantial, it is most certainly not enough to tack an extra 25 years onto your natural lifespan.@Voffvoffhunden How viable of a strategy is going for Whole of Body as your 1st completed tree for every character (even characters without a learning education)? Even if you don't have a learning education improving the experience gain, it should pay off long term since having a large amount of health corresponds to a long life, long life corresponds to more experience gained for other trees.
As a result, taking Whole of Body purely in an attempt to get extra perks in completely different lifestyle trees is counterproductive. That said, there are other benefits in living to be a ripe old age...
I mean, do you really need anything?Granted, this is all assuming you don't need certain perks to keep your council/realm happy.
In all seriousness, while many perks are extraordinarily useful, none of them should be so powerful as to be considered mandatory (and indeed, CK3 has never been balanced with the expectation of players always having a certain perk unlocked).