I generally agree with you, but I would like to comment on the expression you used: "As a scientist, I can't really object to rationality on its own, but it may be worth considering non-rational, transcendent experience as a fundamental psychological need.". I think you would agree that if evaluations such as life-meaningfulness are secondary-properties or qualia like you said then arranging it as a debate between rationality vs irrationality is out of the picture. It is customary to consider various forms of mysticisms as opposed to rationality but it doesn't have to be the case as long as we properly define what is entailed by such experience.

I suppose that the reason people might object to such idea is that they are implicitly committed to a form of positivism and they sense that if people can experience evaluations then the fact/value distinction is undermined. Therefore I think that while it is understandable what you mean when you use the term "rationality" as equated with positivism it would be good for the long term debate to separate those two, since I take it that people like us would like to have it both: science and a form of atheistic mysticism [0].

Ultimately the grand-father of rationality, Plato, was anything but a positivist.

[0] I use the term mysticism mostly because I lack any better term. Evaluative intuitionism is probably the most correct technical term but it has historical roots which I dislike because it was constructed around the single intuition of what is Good, and I believe that we need a wider range of evaluative terms to adequately describe our experiences.