This has to be my least favorite fan card. While overpowered additions like Thengel are broken, they can be a ton of fun to play with. He has a plethora of unique uses in Rohan, Beorning, and The Last Alliance decks. Even Deeping Defender fits in with staging area attack or direct damage decks. However, Seasoned Forager just fits into every Lore deck. Its "restriction" is so simple to avoid, calling it a restriction is harsh. All you have to do is not include Leadership, Mablung, or Arwen Undómiel in your deck. Then, you have a turn-one playable Steward of Gondor that multiple players can use because it isn't unique. Even worse, it is even more overpowered with the new contract: At the End of All Things. Because most resource acceleration is banned, Seasoned Forager is the auto-include option. The final nail in the coffin is Wealth of Adventure. At least if you couldn't find Steward of Gondor in your mulligan, you would have to have a second plan. However, Wealth of Adventure automatically searches your deck for a Skill, virtually guaranteeing Seasoned Forager. Thankfully, Wealth of Adventure is a Leadership card. If it was Lore, I would be seriously disappointed. I still appreciate fan cards and will never stop loving The Last Alliance. However, cards like these inspire no creativity, introduce little deck-building challenge, and break the game's balance. I know another Master of Lore wasn't the right answer, but I would rather have underpowered spice than this bland powerhouse.
Unexpected Courage is probably my favorite Spirit card. It's basically like buying a threat-less hero for only 2 resources! Have a hero with high stats in two different areas (like Glorfindel)? No problem! Just attach Unexpected Courage and you have a powerful quester and attacker. Or if a hero has a good ability and strong stats, Unexpected Courage is a huge benefit. This is an amazing card, a must have in every Spirit deck.
I love sneak attack. It is a very versatile card that can be used in any deck that has leadership in it. The Gandalf Sneak Attack combo is a very powerful combo. I am new to the game, and just played through the Elves of Lorien starter deck, and though I have not tried this card in that deck yet, I am going to find a way to get it in there, because so many of the elves have abilities for when they come into play. Alongside Celeborn and Galadriel all of the Silvan allies coming into play would immediately get boosted for their turn, then be returned to your hand, which can trigger other card effects within SIlvan. It just seems like that would be an excellent way, other than Gandalf, to use Sneak Attack. Great card.
Ironically enough, I am starting to think the best place for Steed of the Mark is actually in a Forth, The Three Hunters! deck, despite it's lack of the restricted keyword. Hear me out.
The two biggest drawbacks as others have stated are the ongoing cost and lack of heroes worth readying with the ability. The nature of a Three Hunters deck means you will have targets worth the readying as well - the guaranteed willpower boost from the contract as well as whatever stat buffs from the restricted attachments they hold will provide some value.
With the cost reduction of the contract resources are very rarely lacking, and once the contract flips they just start to pile up. Spending that pile means the cost just isn't as costly - does it matter if my resource pile doesn't get beyond 3 for the rest of the game? and if you do feel you get in good enough shape you don't need to use it, you can stop.
That being said, it's still not nearly as good as the gold standard in Unexpected Courage, but with the contract it becomes eminently playable as a secondary source of readying, especially running Elfhelm for the stat boosts.