I would love to cross class with Lancer... I find that it would be such a good match with WAR compared to PUG (even in style since they both use 2 hand weapons).
if that would be the case, I'd want to be able to choose between:
- Invigorate, obviously for OT situation where we focus on DPS
- Keen flurry, would make so much sense for WAR to have a buff that increased parry rates
- Feint, applying a slow debuff on mob? good for tanks
- Life Surge, a perfect combo with IB to get more self heals
- Blood for Blood, sacrificing mitigation for damage fit my image of WAR pretty well.

Though B4B might be too much, I feel these would be great fits without breaking the current balance.
Then, give PLD to cross class with PUG so they too get a slight improvements... Cuz cross-classing WAR sucks for them really...