Revelations and Realizations

[Guinevere]

...united the long sundered lines of the half-elven.

Looking at the genealogies, I noticed that in Elrond (and Elros) the lines of all the Elven houses (Noldor, Vanyar, Sindar) come together as well as the lines of all 3 houses of the Edain (Beor, Hador, Haleth) (plus the Maia strain from Melian) And in Arwen, there is in addition the line of the Teleri of Aman (through her mother Celebrian)
I'm sure this is no coincidence!
Because of Arwen's marriage to Aragorn the inheritance of all this nobility will live on in Men.
As Tolkien wrote in letter #144

...the Elder Children, doomed to fade before the Followers (Men) , and to live ultimately only by the thin line of their blood that was mingled with that of Men, among whom it was the only real claim to "nobility".