That last part describes LotR. Gandalf is the DM PC, who has a bunch of hirelings carry the cursed items, and be distractions or cannon fodder.
Frodo carries the ring because Gandalf can't, by his own confessionm do so. Gandalf says, "I can't, because I'd fail my saving throw." One could argue that Sam, Pippin, and Merry start out as henchmen, but if you are reading the book rather than watching the movie, it's clear Frodo is the protagonist. (Aragon is the deuteragonist, sharing equal time with Frodo after he's introduced but ultimately secondary to the plot.)
And the Balrog is a 8+8 HD monster.
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The Istari (incarnate Maia) were forbidden from direct conflict with Sauron and were to advise/counsel rather than be front-line blasters.
Are you trying to lecture me in basic Tolkien lore?
I suspect Gandalf was the "rogue" of the Istari, less wizard and more Arcane Trickster or maybe Bard.
Gandalf was the vassal of Varda Elentári and seems to have been her chief councilor and advisor - an angel of wisdom and light (in both real and metaphysical terms) in service of the archangel of wisdom and kindness and mercy. He seems to have stuck with the plan because of the five chosen he was the only one with the wisdom to do so, although that may not be fair to three of the five as it appears that their lords may have had ulterior motives. Oromë cared more for the "dark East" and its suffering people than any of the other Valar, and Yavanna always cared for plants more than people. And far seeing Mandos may have been prophetically looking ahead to events after the fall of Sauron. The fate of the Blue Wizards and the sum of their acts for good or ill is not something Tolkien fully develops, except that he does say that without their work unseen or and uncelebrated on in the east, the forces at Sauron's command would have been too great for the West to overcome. Their failing IMO and in Tolkien's limited comments on them seems to have been mostly that they were too proud to give up their task, and that they stayed to long in the East, unwilling to yield the fight and too sure of their importance in it.
But that speculation is unimportant to the major discussion, which is the nature of power in the third age, where a wraith is accounted a major power
Meaning Istari are "top tier" creatures, pretending to be lower CR, rather than actually being lower CR creatures. Given that balrogs are a corrupted form of Maia, that CR seems pretty high.
Here you should really read the essay, because you are walking right into the argument that it eviscerates.
There are Ring Wraiths, that can only be killed after being injured by specifically enchanted blades, who can pop up anywhere. Unkillable threats seem pretty high level.
Basic wraiths are 5D and can't be harmed without magic weapons. Why does it seem that they should be "pretty high level" just because you can't kill them without a +1 weapon, that almost no one has?