I think you’re fundamentally misunderstanding Kierkegaard’s philosophy if that was your takeaway. He was reacting to record social mobility at the time in his home of Denmark; and wanted to try and convince people in his community to not be impressionable and beholden to other people’s systems of morals and ethics. Instead, he wanted people to pursue understanding of their innermost desires and ambitions, regardless of whether they were popular or considered morally or ethically right (hence: the “teleological suspension of the ethical”).

Love Sartre, especially his Marxism. But what about Heidegger?

I actually love Nietzsche, especially his nihilism. But I don’t usually associate him that strongly with classical Existentialism. After Kierkegaard, I would say Heidegger would be next.

Yeah, no shit? Kierkegaard is the father of Existentialism.