Your standard trap deck, using secrecy to choose when and what to engage. Damrod's trap discount and Prince Imrahil's action ability cover pretty well for the lack of a third hero.
Prince Imrahil is great with traps as we get a, somewhat, reliable way to manipulate enemies in the staging area with Mablung and Guardian of Ithilien, which allow us to attach our traps on more relevant targets. Because of that, unless we're in dire need of willpower, we should avoid playing Mablung.
Our willpower is deceivingly low, but we got Followed plus Forest Snare, and Emyn Arnen Ranger to help us quest.
Our combat doesn't have the biggest numbers, but what we lack in raw stats we have in tricks on our sleeves.
For defense, we have the option to not engage, with Ranger Spikes; cancel attacks, with Forest Snare, Coney in a Trap, and Feint; or to simply defend, with Beorn, Boromir, and Defender of Rammas.
We should focus on dealing with our enemies on a one by one basis. In the earlier stages of the game, we can use Prince Imrahil's action to grab an ally to attack with or use one of our tricks to avoid the attack. While on the later stages, we might have had the time to gather a few allies to attack.