Well for that matter, don't they all have pretty basic "cookie cutter" personalities, but they're given dimension through personal episodes? Sure she can be less exciting than a Pinkie invasion, but why isn't she featured more and built off of?
I find myself agreeing with her more than Rarity or RD, although they all have that mutual ecocentric personality.
For that matter, wouldn't her stubborness make her the most individual of characters? I mean apart from asking for help and whatnot, she has VERY clear opinions on things and would be the least likely, in my opinion, to be persuaded to do something not typical of her.
I was tied against RD and Fluttershy for a while, but I feel like AJ being less-appreciated has made me notice her more and made her my favorite.
The belt buckle does sound awesome, though! You'll be able to match the RD with almost anything, but I do wish a kicking AJ was made