Oh, spend more TP to get the same enmity as well as not being able to focus on non-enmity combos as much as DRK. Duh, I wasn't thinking, haha. Yeah, assuming all enmity multipliers on Rage of Halone/Power Slash/Butcher's Block are the same (and I'm assuming they are: 5x), that certainly is a problem.
Is there testing that someone has posted somewhere to prove that Flash is less enmity than Unleash or Overpower? To be fair, Overpower probably should do a little more enmity because of the huge TP cost. Then again, maybe WAR having no TP problems outside of AoE enmity generation as well as being able to use Flash balances that already?
Btw, there is literally a "Rallying Cry" ability in the game already: http://xivdb.com/?skill/1561/Thrill-of-War
Honestly, a lot of the PVP actions could have been put to good use and retooled as the new job actions in Heavensward, but I can understand why they're wary of enabling them in PVE even in an altered form. I really, really hope that for the next expansion they remove cross-class actions (the whole system is a total failure once you promote to a Job anyway) and replace them with some form of the PVP actions. I thought they'd do that for this expansion, but oh well.