Nice points!
Yes,their number might have increased in the peace of Aman and Tol Eressea during the Second and Third Age,but not to a really high pace,since they did not breed frequently and did not have many children.
As for the seperate Kings...Setting apart the subgect of Noldorin kingship,the Teleri have also a little problem .Would it be Elwe,their original leader,Olwe,their next king(persuming he did not die), Dior or Elrond -the Children of Luthien are the answer to anything
-?
And if Olwe still ruled the Teleri,would he bare to see on the Noldorin throne the unwilling slayer of his people-a.k.a. the in-all-other-means-respectfull Fingolfin-?
Ah,it is difficult living in Aman!