Ring Mail is a surprisingly versatile way of keeping your defenders alive and kicking. Dwarves and Hobbits often really need the defensive help and this can attach to any character, not just a hero. Bombur, Dori, and Bilbo are all good targets, not to mention the multitude of Dwarf allies with big health pools like Erebor Hammersmith. Very good.

Erebor Battle Master was completely overpowered in a Dwarf deck before his errata (spoiler alert: he still is). You could plop him down and he'd swing for a minimum of four for the rest of the game. As is, he takes a couple of rounds for him to get pumped up, but once you get your dwarf swarm going, the Battle Master rivals a Booming Ent trio. Just let him sit there, making Dain's boost look insignificant, staring down (up? he is a dwarf) orcs with that one eye of his.

Fresh Tracks, much like Hail of Stones, is surprisingly not a bad card. You may be looking at me funny, but the ability to keep an enemy in the staging area that one extra round can make a big difference. But don't expect the damage to kill the enemy as much as possibly help next round when the enemy does come down. Who knows? Maybe you could fit it into staging area attack deck.

Since it's a response, does this allow you to dispatch some Mirkwood type bats that have 1 HP and surge (like a questing Thalin) and prevent the surge effect? —
Ah, I think I answered by own question; the timing would make the difference. Thalin says to apply the damage "as it is revealed by the encounter deck" where Fresh Tracks states "AFTER an enemy is added to the staging area" —
Correct. Effects work in this order: passive, forced (when revealed, surge, doomed), response, action (only in an action window). —

Erestor is one of my favorite allies, and a good one too. Four resources in leadership shouldn't be hard to stomach, and Erestor fills one of his home sphere's weaknesses: card draw. Suddenly, all of those dead copies of Steward, Stone, StwB, or whatever are accelerating your hand; all while you're getting an extra two willpower and a sizable hit-point pool. Elven Light and Galdor ally add to the madness.

Resourceful is probably the best example of what secrecy could have been. An extremely versatile card that is bonkers good in secrecy, and relatively playable if not. Sadly, most secrecy cards are only worth it while you're under that ever-important twenty threat threshold. Still, an extra resource a round is undeniably good, so if you're planning to run the long game; Resourceful might be worth the deck space.