The damage per cost is the same as the other classes.
It counts as a weapon - some pirate cards (and others) works well since they have a synergy with weapons.
There are 3 I can think of all of which are round 3 or 4 plays unless you coin. So you can coin out and weapon up round 1. Round 2 drop the 2/1 charger, a 3/3 or a 3/3+taunt. All of which are sound openings; if you're lucky to draw as such AND if you're lucky enough to go 2nd. Unfortunately I'm not... I never am. And all of which can be done with similar uncommons without needing to waste a coin or round to pop 2 mana for a hero power.
I'm not seeing an advantage personally.
Either way you're still left with a 1/2 weapon which can't be used for anything other than plinking your opponent, provided he doesn't have a taunt (YAY! Taunts!!! /rolleyes), or trading damage with a */1 minion. Meanwhile the mage power can drop that */1 minion for the same mana cost, not being forced to trade damage and ON TOP OF ALL THAT doesn't have to worry about Taunt.
It seems to me that the Rogue Hero power is an uber gimped version of Mage.
If I *have* to trade damage with my otherwise useless Hero power, at the very least make it a 2/1 weapon so I can at least trade up with a 3/2 minion.
I dunno. I've wracked my brain trying to figure a way to turn my Rogue's Hero power to my advantage and I just can't find one aside from poison. And that just sucks in my mind.