Peterson & Park (2010) provided a commentary on Kenrick et al (2010) whereby they pointed out that although the revision makes an important contribution by grounding the hierarchy in modern evolutionary thought, it may be premature to remove self-actualization from the hierarchy by reducing it to other needs associated with status and reproduction.
We suggest that it is premature to jettison self-actualization from this revised version of Maslow’s hierarchy. We write from the perspective of positive psychology, which regards what is good in life to be as genuine as what is bad (Peterson & Park, 2003). What is good is not secondary, derivative, illusory, epiphenomenal, or otherwise suspect—at least until the data show otherwise. In their revision of Maslow’s hierarchy and their dismissal of self-actualization as a motive in its own right, Kenrick et al. seemed to reflect business-as-usual psychology by reducing what is good to something more mundane and perhaps not so good.
However, Kenrick et al. mentioned positive psychology in their article and concluded that their evolutionary perspective is consistent with the view that human nature indeed has positive aspects. So, their revised pyramid may well accommodate the various emphases of positive psychology. And someday, if we take the pyramid metaphor literally, psychologists may follow the earlier examples of Egypt and Mexico and build several, including one that reflects Maslow’s (1971) deficiency needs and another one that reflects his growth needs.
It is important to note that Maslow's (1943, 1954) five-stage model was expanded to include cognitive and aesthetic needs (Maslow, 1970a) and later transcendence needs (Maslow, 1970b).
More can be read on that in an article by McLeod (2018).
So answering your question on generalizing the top portion of the pyramid by Kenrick et al. beyond peaking out at parenting may not be relevant as Maslow went beyond parenting with his expanded pyramid.
Maslow, A. H. (1943). A Theory of Human Motivation. Psychological Review, 50(4), 370-96. doi: 10.1037/h0054346
Maslow, A. H. (1954). Motivation and personality. New York: Harper and Row.
Maslow, A. H. (1970a). Motivation and personality. New York: Harper & Row.
Maslow, A. H. (1970b). Religions, values, and peak experiences. New York: Penguin. (Original work published 1966)
McLeod, S. A. (2018). Maslow's hierarchy of needs. Retrieved from: https://www.simplypsychology.org/maslow.html
Peterson, C., & Park, N. (2003). Positive psychology as the evenhanded positive psychologist views it. Psychological Inquiry, 14(2), 141–146. Retrieved from: http://www.jstor.org/stable/1449822
Peterson, C., & Park, N. (2010). What happened to self-actualization? Commentary on Kenrick et al.(2010). Perspectives on Psychological Science, 5(3), 320-322. doi: 10.1177/1745691610369471