In my view, the duel between the Balrog and Glorfindel was basically rewritten as the duel between Gandalf and the Balrog, even to the details of the Balrog tumbling down from a great height and bouncing off the side of the mountain (because either his wings were injured or were shadows incapable of supporting his weight or.... never mind).

I would have liked to have seen Tolkien rewrite the duel of Ecthelion and the Balrog. Impaling a foe on the spike of one's helmet seems inelegant.

I would love to see a more detailed version of Ecthelion Vs Gothmog aswell, it would be fantastic. I second your notion sir! Two of the most renown warriors of Middle Earth, how glorified, yet how satisfying.

And the recovery of the hero's body by a Great Eagle... and the fact that both were reincarnated.

Ok, so Lothlorien would be in trouble in trouble if the Balrog or Smaug came there and attacked? What about "the power that dwelt there that was too great for any to overcome unless Sauron came there himself"? Shouldn't this apply to any power lesser to Sauron (which would include Smaug & the Balrog)? And if Galadriel was indeed more powerful than Glorfindel spiritually, then wouldn't it be obvious that she was more like to the level of a maia than Glorifindel who was enhanced?

Yes, in fact I believe I posted something to this effect earlier. The parallels between Gandalf and Glorfindel are pretty striking, even beyond the Balrog fight.

As to the Balrog coming to Lothlorien, this seems to make no sense. Certainly the Balrog would not be able to overcome the protection of Lothlorien, since only Sauron (and probably then with the Ring) would be able to do so. In fact, it seems noteworthy to me that the Balrog stayed hidden in the deep recesses of Moria. There is no record of him ever venturing forth that I know of...

I read somewhere, perhaps here, the theory that there exist in the Legendarium a class of "heroes" known as White Riders. That theory included both Glorfindel and Gandalf within this category, based upon their apparent power over opponents while on horseback and the fact that both seemed to possess an inner white light.

I think that the reason that it would be a very dangerous thing for a balrog to come to Lothlorien has less to do with Galadriel’s ability to fight either of them, and more to do with the fact that Lothlorien is a forest and balrogs are ancient demons of flames. Whatever other powers she had, I doubt automatic sprinkler system was one of them. ;)

Being slightly more serious, a tightly packed forest is probably not the best place to fight a large beast, simply because of the lack of maneuverability. By the time you would have been able to get close enough to take a swing at it with your sword, half the land you’re fighting on might be on fire. I feel it important to note that most of the places where balrogs were fought were either mountains, cities in mountains, or barren desert-like places. So, as long as you dodged it’s whip you weren’t up in flames. Plus, with Lothlorien the balrog wouldn't even have to enter to destroy it.

The elven rings don't enhance their bearers in terms of "individual powers". That being said Galadriel, who stood along with Melian much more time than Glorfindel with any Maiar, was capable of destroying a fortress and eradicate all darkness in that place, said to be the greatest Eldar of the Third age and the greatest of all times save Feanor would be more powerful than Glorfindel for sure.
Galadriel in the Third Age would use Magic against a Balrog and would probably demolish him.

I lol'ed at this one, haha.