[Aiwendil]

Perhaps:

But {think not, Ælfwine, that} the shapes wherein the Great Ones array themselves are not at all times like unto the shapes of kings and queens of the Children of Ilúvatar; for at whiles they may clothe them in their own thought, made visible in forms terrible and wonderful. And {I myself, long years agone,} some in the land of the Valar have seen Yavanna in the likeness of a Tree; and the beauty and majesty of that form could not be told in words, not unless all the things that grow in the earth, from the least unto the greatest, should sing in choir together, making unto their queen an offering of song to be laid before the throne of Ilúvatar.

It has the advantage that it minimizes the addition.