Relative Powers

[Raynor]

yet Feanor is named specifically Mightiest of the Noldor.

I don't think that might in itself is too much of a thing. Since he didn't use his mind, but rushed foolishly into battle, loosing his life for nothing, he only proves his "brutish" force. I would place Fingolfin above him, for his abilities, and deeds:

Originally Posted by Of Eldamar and the princes of Eldalie, Silmarillion

Feanor was the mightiest in skill of word and of hand, more learned than his brothers; his spirit burned as a flame. Fingolfin was the strongest, the most steadfast, and the most valiant.

Okay, Finrod was killed by a single werewolf of no great stature whereas Fingon is on par with Gothmog and is brought down by a dirty tactic and Finrod is tougher?

That was no small feat, considering esspecially the condition in which Finrod was:

But when the wolf came for Beren, Felagund put forth all his power, and burst his bonds; and he wrestled with the werewolf, and slew it with his hands and teeth; yet he himself was wounded to the death.