[Formendacil]

Nienna.

Definitely Nienna--and not just because I'm especially fond of the Downs member of that name. The Vala herself is awesome. Not that the others aren't, mind you. Varda Elbereth will always have a place, thanks to Frodo and The Lord of the Rings, but in terms of character, I think I can be said to follow Gandalf, and prefer Nienna.

Something about weeping over the wounds of Arda strikes me as profoundly Catholic... though I'm not sure I want to get myself into any sort of an argument there. I think, additionally, that despite the definite identification that could be made between her and "weepiness," Nienna is, undefinably, the strongest of the Valar--not just the Valier, but the Valar. She's the least shocked, despite the most offended, by the marring of Arda.

Also the whole fact that she's probably the one Melkor scorns most, but the one his opponents (eg. Gandalf) have the most to learn from.