Luthien weilding Vilya

[Belegorn]

Gorthaur, I do not recall Lúthien ever being mentioned as the prime Elf. I will cite several texts that seem to me to clearly say that Fëanor is above all others the foremost of all the Children of Iluvatar.

"Fëanor was made the mightiest in all parts of body and mind... of all the Children of Iluvatar" [Sil, p. 112]

"his likeness has never again appeared in Arda... Thus ended the mightiest of the Noldor" [p. 125]

"he was mighty in body and in all the skills of the body, and supreme among the Eldar in eagerness and strength and subtlety of mind" [Morgoth's Ring, p. 236]

"This child is the greatest in gifts that hath arisen or shall arise among the Eldar." [p. 240]

"Aulë nameth Fëanor the greatest of the Eldar, and in potency that is true." [p. 247]

He was skillful, cunning, and astute in mind, and his potency is not matched by any of the Eldar according to the Valar. It was mentioned that it was not known of what substance the Silmarils were made of. It would be interesting that this creation even baffled the Valar who had a hand in the building up of Arda.

Originally Posted by Gorthaur the Cruel

I think Narya best suites him because Finrod was very wise

In any case I do not think his possession of it would necessarily prevent Sauron or Morgoth's servants from overrunning a realm in which it was held.

Originally Posted by Gorthaur the Cruel

True... which means the Balrog, Saruman, Smaug, Witch-King, etc. cannot penetrate or destroy Lothlorien, as they are not as strong as Sauron.

I'm not sure if this is necessarily true. As Zigûr mentioned, Melkor poured his strength into his servants and he had powerful servants like the dragons, and the balrogs were Maiar like Sauron. I think these with their servants/soldiers could probably take out any of the Elven realms where the Rings were held.

I do agree with you about the Witch-King, for it is said that while he was searching for Gollum and the Shire, "the power of the White Ring [Nenya] he [Witch-king] would not defy, nor yet enter into Lórien." [Unfinished Tales, p. 354] Also in this same chapter Gandalf believed Sauron could overthrow Lórien and Rivendell, "And those places might have fallen, I think, if Sauron had thrown all his power against them first" [p. 345]

Originally Posted by Gorthaur the Cruel

Luthien with her maiarin blood with Vilya might be able to withstand a ringless Sauron indefinitely

I'm not so sure about this. Huan the hound saved her from Sauron when they came to save Beren. Although she and he did take out his servants. Even a ringless Sauron in the 3rd Age was believed by Gandalf to be able to take out Elrond's and Galadriel's realms.

Originally Posted by Gorthaur the Cruel

But with Gandalf, although he is a maia, the body that he inhabited retricted much of his powers; his body was also quick to tire like that of an old man

True, but remember his battle with the Balrog. I do not think you will find in that battle that he held back and he was still taken out of commission for a while.

"There was none to see... what would they say in song? Those that looked up from afar thought that the mountain was crowned with storm. Thunder they heard, and lightning, they said, smote upon Celebdil, and leaped back broken into tongues of fire." [The Two Towers, p. 125]

Originally Posted by Gorthaur the Cruel

I believe they would wage war against the guardians of the Three and would want to wield the rings themselves

Perhaps, or this knowledge of ring-lore would be shared or even known by someone like Curufin, "who inherited most of his father's skill of hand" [Sil, p. 63]

Also read Zigûr's post because the approach between the two Lord's would be different. Sauron's power was mostly poured into the Ring which is why it could be his undoing if destroyed. Morgoth poured his strength into various things and therefore in his servants you had much to worry about. As far as I know, Melkor was more likely to avoid any physical confrontation anyway. After he disposed of Fingolfin he never left his chambers again until he was taken by force. Sauron did go out several times to meet his enemies and the one where he did the most damage was in his deception of Númenor and its downfall when he went there as a voluntary prisoner. In this case he used deception because he knew his servants, none of them, could stand up to the Númenóreans.