As a general rule, cards have as much attack and health as their cost. Charge is the exception, which effectively doubles the value of the attack stat and makes a 3/1 perfectly runs off of twice the attack value plus the health instead. To deal as much Charge damage as the cost, it would have as much attack as it’s mana cost and only a single health point.
 
Of course, 6 mana is where the value starts dropping a little bit, hence the fact that Reckless Rocketeer is a 5/2. Of course, class cards are more powerful than neutrals like our Rocketeering friend, but not usually by this much.
 
She doesn’t really fit in Rogue either. There’s not much less subtle than a rainbow maned Pegasus charging at you.

@DaringDo42  
I feel like the health needs to be changed as well, since it can be taken out by spells with low mana cost like Soulfire and Darkbomb with a combo of Mortal Coil.

I’d bump the mana cost to 7. Reckless Rocketeer is a 6-cost, 5/2 charge minion, and this has better stats.