I will freely admit that I go back and forth on my feelings on this game; and that's probably not a good thing. I really want to like it, but there are things about it that drive me crazy.
Currently, the one thing that is driving me crazy: it seems that recent scenario design is just "more of the same". Threat, nasty treacheries, hard-hitting monsters . . . and more threat, nastier treacheries, and even harder-hitting monsters.
I was hoping for a change in direction with The Hobbit and with Heirs of Numenor, but the previews here for both sets are MOTS: more threat, nastier treacheries, and even harder-hitting monsters. The original set had some Doomed and Surge cards; the new sets have even more Doomed and Surge cards. The original set had nasty never-want-to-ever-see-them treacheries; the new sets have even nastier never-want-to-see-them treacheries. The original set had 6/3/9 monsters; the new sets have 7+/3+/12+ monsters. This is supposed to be compelling gameplay . . . how?
One problem is that this just feeds into the current meta-game of sticking with a very narrowly defined does-it-all strategy that can routinely dispatch most quests with little difficulty, and is only challenged by the most brutal swarm of hard-hitting treacheries and monsters. Greetings and Gandalf for threat reduction, Test of Will so you never have to worry about another treachery again, and loads of dwarves with axes and armor to finish off the hordes of monsters. There is little flexibility and little innovation, and frankly, it's boring.
Even worse, it's unthematic. If you never read Tolkien's original works and your only experience was from the LCG, you would think it was all about bands of dwarves roaming the land hacking apart impossibly tough monsters while occasionally stopping in to rest at the local elf-run tavern. Subtlety: none, really. Diplomacy: none. Magic: what magic? Interactions between heroes: they're all in this together and the best of friends. Humble people succeeding against impossible odds: why bother with the hobbits when Gimli and Glorfindel can handle just about anything?
My complaint is about scenario design, but now that I think about it, it may simply be that the deeper game design is flawed. They do not have a solution, for one thing, for power creep. Hence the need for more threat, more nasty treacheries, and harder-hitting monsters. This is a problem the designers should have seen coming a long way off, but they made no considerations for it in the game design. (Why not just leave the power creep in place and consider it part of the game? Because the nastier the encounter decks get, the more of a chance there is that the player will lose simply by virtue of what is drawn out of the deck in the first few turns. Since the player's power scales up slowly over time, but the encounter deck can hit the ground running - particularly with Doomed and Surge - the more difficult the scenarios are, the greater a factor luck plays, which is a bad thing.)
The other problem is that the designers gave themselves relatively few tools to work with - locations, monsters, and treacheries aren't that much when you come to think of it. You travel, fight, and reduce threat, and that's about it. And what's worse, the mechanics on many of the cards are very straightforward: place progress tokens, do damage, reduce threat, cancel a "when revealed" card. The game has nowhere near the complexity of interaction of mechanics that Call of Cthulhu has, let alone Android: Netrunner, where cards interact in interesting ways, which encourage the development of deep strategies. And the encounter decks are worse than the player's decks; there is little to no interaction between cards in the encounter decks, so all the designers can do is just turn it up to "11".
I will give the designers credit for attempting to strike out in a new direction with Secrecy. But that seems to have gone nowhere, as most players simply ignored it, and so it's back to the standard approach. That's unfortunate. I'll keep watching this game, but right now it just isn't a temptation to get the more recent releases, when they're just Mirkwood with Doomed and Surge and more hit points.