In my opinion, the best cross class skills for WAR highly depends on which content you are doing.

Flash is useless for Ravana EX, but it is useful for Bismark EX, for example.

When we pop berserk to hit that carapace thing on Bismark's back (as we all should) we may be under the Pacification when the next set of adds spawn.
Sure a healer can remove that, but if that's not the case for whatever reason, Flash the add(s) for initial aggro and when GCD is back pacification should be gone.

Awareness used to be useless for most content except maybe Shiva EX (bow phase) and T11 if you tanked the cube add (which crits a lot).
But it definitely deserves more attention now, since it completely negates the bad effects of Raw Intuition.

I still like Second Wind, and it scales with STR. We did get a similar skill under Defiance to heal more HP than a Second Wind, but having both is definitely not bad at all.



Featherfoot is very unreliable, it is only slightly useful in PvP.

Even Haymaker had its use for WAR back in the days Garuda EX was still hard.
Garuda and sisters miss a lot, and you get it to proc and all of them are susceptible to the Slow effect.

MAYBE Haymaker could be used for the small adds in Ravana if you dodge one of their attacks to proc it, and slow down the add that casts a buff on ravana giving dps a little bit more time to kill it.
(I doubt that's the case but would be interesting if worked)