BB spam is actually the worst possible rotation you can do as a WAR: it's got the lowest damage (barring just spamming SP) and isn't even the best enmity generator.
WAR has 3 basic useful rotations:
SE>BB>BB>BB: this is your highest enmity rotation. Use it at the start of the fight to generate your enmity cushion (if you're not doing the opening attack string that I use) or when you have someone riding your ass.
SE>BB: this is your highest damage rotation that also generates strong enmity. Use it when you damage taken isn't really an issue (re: when you don't need the SP debuff).
SE>SP: this is the rotation you use when you have your enmity cushion or when you are offtanking. It maintains both debuffs with 100% uptime and does the second highest damage of your rotations.
Overpower generates more enmity not because it deals damage. Flash could just as easily generate more enmity than Overpower if the devs cranked up the enmity value on Flash but they didn't. In fact, against enemies with dramatically beefed up damage resistance, Flash actually generates more than Overpower because Flash simply generates enmity based upon your attack power (which also means that it doesn't benefit from FoF) whereas Overpower generates enmity based upon the damage you deal (damage absorbed by an absorb shield is still valued at its full value even if it throws up a 0).Overpower is a conal shape AoE aggro tool. It's superiority over Flash is that it does damage, and thus generates more aggro than Flash
WAR cds are weaker but on shorter CDs which does not mean that the WAR CD suite is inferior. If you use them like you would PLD cds (that is to say, holding on to them until you really need a CD) and using that as your point of comparison, you're doing it wrong. The best way to use the WAR CDs is to use them actively while staggering them. By staggering them, you can basically have some kind of CD active on you 100% of the time. PLD can't get anywhere close to that which is why they have to pick and choose when to use their CDs. A WAR that doesn't have 1-2 CDs on CD at any point in time (at least while they're tanking) is doing it wrong.Warriors don't have as superior defensive cooldowns as Paladin