For "Radiant" (shining, glowing, sparkling)
The "obvious" choices:
Two Trees of Valinor - The most obvious of the obvious choices. 'nuff said.
Arien - an excellent choice, if there weren't Telperion and Laurelin played as well, for neither Arien or Tilion carry with them the original light but a faded version of it.
Phial of Galadriel - an excellent choice (well, not perhaps so sparkling but...), if there weren't Telperion and Laurelin - and Arien - played as well, for the phial is just a reflection of a reflection of the light of the Trees - so like two times removed from the original.
Varda - The only possible competition to the Trees if you think of her as the creator of the stars themselves - but she is not the stars as she is their creator: so unlike the three others she doesnt radiate but creates things that radiate (wasn't she initially the dew-collector for the trees?). Is that better or worse than radiating yourself - that's up to you
tp.
Good or decent choices but not like the first attribute I'd give them (if you want to think outside the box, then you might find a good candidate from here):
Romenna - Must be one of the most radiant cities ever built, and especially because it became the safe-haven (
) of the faithful later on...
Tuor - if he manages to be picked by Ulmo, to become the leader of the "House of the Swan Wing" and to be the only human counted as an elven kindred, then he has to be quite radiant.
Nessa - dashing speed and great dancer, not that far-fetched for radiant.
Ulmo - I think all of the Valar must be radiant in some way but I wouldn't think I would go using that term on Ulmo in the top-fifty choices for descriptions on him.
Ithilien - Yeah, you could say that, maybe, possibly, on some fine times. But it is in the end a forest.
Hmm...
Golfimbul - Well, if you think losing your head into a rabbit-hole is radiant, then why not...