I've always had difficulties in coming up with a decent Gondor deck. While there is plenty of cards for the trait, they are split accross all spheres and support different strategies. In addition, most of the heroes are high threat, double as important unique allies, or both. Nevertheless, with the last cycle, I believe we got some cards that help building around Gondor. The key additions are Heir of Mardil and Mablung.
This deck is a leadership/tactics deck that emphasises resource acceleration, ally mustering and global boosts. For regular quests, it uses Imrahil, Mablung and Theodred as the hero line-up. For battle questing, swap Imrahil for Leadermir, for siege or strong defensive requirements, Beregond instead of Mablung. This deck is certainly not top tier, but it has defeated all quests from the VoI deluxe, HoN, as well as Druadan Forest. Steward's Fear was not a success so far...
It should work for most quests not putting on too much early pressure, or extreme ally hate.
Heroes:
Imrahil/Boromir (Leadership)
Theodred
Mablung
Allies (23)
Squire of the Citadel (x3)
Pelargrir Ship Captain (x3)
Guardian of the Citadel (x3)
Herald of Anorien (x3)
Faramir (x2)
Defender of Ramas (x3)
Envoy of Pelargrir (x3)
Gandalf (x3)
Attachments (15)
Steward of Gondor (x3)
Heir of Mardil (x3)
Visionary Leadership (x3)
Shield of Gondor (x3)
Gondorian Fire (x3)
Events
A Very Good Tale (x3)
Sneak Attack (x3)
Valiant Sacrifice (x3)
Feint (x3)
Looking forward to your suggestions!