Authority of the High King

[akhtene]

To my mind the history of Noldor shows that the authority of their High Kings wasn't great at all.

What is the power or authority of a king based on? Birth-right (eg. Aragorn) or great services to his people. But neither is true for the first of the Noldor kings, Finwe. He was merely chosen by Orome, together with Ingwe and Elwe, as ambassadors for their people in Valinor.
Later the elves followed these leaders "who afterwards became kings" but I doubt that the people owed much to them. In case of Finwe's children, those were no better than any other elf, with the same virtues and follies (and a lot of those), and besides much younger than others. (Well, I'm not sure the latter mattered much for the immortal elves)
But anyway, as they were accepted as

nominal leaders at "group things."

they hardly were granted any influence or power to raise their people to act against their wishes or personal ambitions.