I am playing through the adventure packs in the order of release, and am about to start A Journey to Rhosgobel (Shadows of Mirkwood cycle).

Many of the new cards in the Shadows of Mirkwood cycle have effects that utilise traits, such as the Rohan, Creature and Eagle traits.

At this stage I'm unsure whether any of these traits are strong enough to build decks or combos around them, and I am curious to know at what point in the game's evolution other players started to build decks around a particular trait?

Is it to early for me to be thinking about traits, or are they something I should be factoring into my deck building process now?

Creature: There's no creature synergy in the game at all except for Radagast.

Rohan: By the end of Shadows of Mirkwood you should be able to have a decent Rohan deck, but anytime before then it won't be strong enough. Voice of Isengard and Treason of Saruman bolster the Rohan trait quite a bit.

Eagle: Eagle synergy is accessible with Eagles of the Misty Mountains and Support of the Eagles/Boromir.

Thanks! I'm really looking forward to the Eagle synergy you're describing. Only a few more scenarios to go and I'll have those 3 cards. It seems like the Tactics sphere is getting interesting during this cycle. The Rhosgobel quest, which I am about to begin, seems like it was designed for an Eagle-heavy deck.