[Belegorn]

1- I think that there would still need to be a most skilled craftsman and I believe Feanor's grandson who forged these Rings, with the aid of Sauron, was closest to his grandfather in skill of hand. I can see some sort of venture to stop the fading being looked into since they were not in undying lands which was more their abode than the lands of Middle-earth.

2- I would think that Beren would probably be granted a fate like the Elves then and would have to come back as an Elf. If Finrod was sent back he would be mightier than he was when he was felled by Sauron in battle.

3- I like Felagund with Narya since he seems to be an Elf of the other people.

4- Luthien might wield the strongest Ring, but Galadriel would still be the mightiest Elf. Even when Elrond bore it she was still the greatest Elf in Middle-earth. Albiet, so long as Feanor is not around she is the top Elf. However, it is clear that no power save Sauron's could penetrate Galadriel's defenses in the 3rd Age. I think therefore that even in the 1st Age with these Rings of Power Sauron could breach the realms where the Rings were held in possession. Remember, Sauron may have been a servant but he was still a mighty Maia. It is clear that Elves can match the Maia as we have seen with the feats of the Noldor in the 1st Age. Obviously aside from Galadriel the new bearers are stronger than Elrond, however in the 3rd Age Gandalf wielded a Ring and he would clearly be comparable to any of them. Personally I'm not sure I can see Luthien ruling any realm. She does not seem the type to want to run a principality.

What of the sons of Feanor, how would they feel about these things? I don't know. Would the curse of Mandos work its way into this new discovery? I believe that a diminished Melkor is still stronger than most in Middle-earth.

Also unlike the One these Rings were made for preservation. So they may have some use in the defense of one's realm they are not meant to be tools of dominion. That's not to say that they cannot be used to aid in war as Gandalf could inspire hearts and light a fire under his men with his Ring.