Este,
I agree.
The one "star" that I've heard mentioned as possibly being a planet is Elemmirė. This was one of the lights that Varda used to welcome the Elves to Arda upon awakening. The Encyclopedia of Arda says this may actually be the planet Mercury. However, they don't list a source for their statement other than to refer generically to Tolkien's notes. I can't find any reference to this in the Letters and I have temporarily misplaced my index to HoMe so can't check it there.
(If you could see the state of my house, you'd know why I am having difficulty locating this index!
)