I still find it hard to believe that many of the places selling physical cards are still asking somewhat outrageous money for cards mostly in the latter 3 major sets, Hunters, RoS, and T&D...
Maybe I will get lucky and somebody that has the latter sets and looking to get out altogether might be willing to let them go cheap...I know wishful thinking.
Even with a dead card game, it is simply supply and demand. The latter sets were produced at such limited quantities--Decipher was mired in legal expenses and had laid off almost one hundred employees--that they have remained hugely collectible. Decipher needed every set to be a financial success and, after losing the majority of play-testers, increased the power of cards in an effort to drive sales.
Obviously you will play the game to your meta, but I would recommend focusing game play to the earliest formats: Fellowship, Towers, Towers Standard, Movie, and War of the Ring Standard. If everyone is playing decks with, for instance, cards from 1-3, then you don't need to worry about the bloated power of the later sets.
You can see the power creep with the Shadows block reset of the game (compare
Uruk Guard and
Uruk-Hai Guard, for instance), but it was actually happening as early as set 8 (just compare an
Fierce Witch-King with the
fierce, enduring
Castamir of Umbar).
Like I said, you'll do what works for your group. But the game is a lot more fun when everyone is playing on the same level and it isn't that one guy happens to have a base strength 10 Aragorn because he scoured eBay until he found something he could justify spending big money on. I've suggested it once and I'll suggest it again: King Standard (sets 1-7) is the most fun and balanced format, in my estimation.
Best,
-wtk