For Warrior: Mantra or Awareness?

[Kitru]

The effectiveness of Internal Release scales with your damage.
The effectiveness of Mantra scales with your healers' throughput.
The effectiveness of Awareness scales with the mobs' damage.

Internal Release helps you with enmity generation and damage. Any potential burst healing on Inner Beast that it provides is unreliable at best. Remember, it provides increased crit rate; not a guaranteed crit.
Mantra provides raid healing utility. The personal contributions that it provides are small enough that you wouldn't want to burn it unless more than just you are taking damage or you have absolutely nothing else to use.
Awareness allows you to stabilize your incoming damage. It won't reliably mitigate incoming damage but it will make it easier for your healers to predict how much damage you're going to take over the time interval because you've, effectively, placed a cap on the damage variability.

Personally, I plan on using all 3 once I level up PGL high enough. My loadout is going to be Convalescence, Featherfoot, Internal Release, Awareness, and Mantra. Right now, I've got Provoke and Second Wind in place of Inner Release and Mantra, but only because they're the least bad of the remaining options.

Flash is rubbish for a WAR because we've got an mp pool so small that it can only be used 3-4 times before you run out of mp and WARs don't have Riot Blade to build that resource back up. It's, effectively, a mediocre threat generator with a limited number of charges over the course of an entire fight. Provoke is only useful as a tool to regain threat after you've died and been rezzed, which, in my experience, doesn't generally work out well *anyways* because it's pretty much always easier to just let the OT take over tanking duties. Either that or a tank death is effectively a wipe even *if* you could get aggro back immediately (since it takes 8 seconds to cast Raise, which is more than enough time for a raid boss to chew through a whole slew of DPS). Haymaker is a waste thanks to the DR on the slow (which is the only good thing about it), and I'm pretty sure that Second Wind's heal scales with Mind rather than anything WAR gets so it's, for all intents and purposes, a static ~600 point heal on a 2 minute CD no matter what gear you're wearing (it's unaffected by Berserk and the effect is labeled as "Cure potency", of which every *other* ability labeled as such uses Mind); once you've hit your mid-30s, Second Wind is effectively pointless to keep around.