I, with my small knowledge, shall now come and interrupt your peace and harmony

Because I disagree with you all. I think that Lórien of Valinor was fairer.
It was in Valinor. The reason might sound stupid, but in Valinor all was basicly more beautiful. Nothing never died there (except some elves, but we won't discuss it now).
The Valar, Lórien and Estë lived there. I suppose that they had more power to make their Lórien beautiful than Galadriel had with Nenya.
And all the light didn't go with the two trees; the sun came, and the moon. And they stayed in Valinor longer than in Middle-Earth.
So I can't see any reason why Galadriel's Lórien would have been more beutiful than Lórien of Valinor.