I see Rumble as a gangsta type personality due to the pose he made in Marks and Recreation leaning his back on the wall, making a sly smug, sassy behavior, and toughness and outgoing. Even a lot of fillies in Ponyville want to get jiggy wit it with him. He (in my head canon) has the gangsta personality
 
While Soarin, is the Bad Boy type like Thunderlane, Sky Stinger, and Flash Sentry. Since Soarin is a Wonderbolt, and has a crush on girly girls (like Fluttershy) makes him a bad boy. His toughness also shows it along with his hair. (Although Thunderlane is much more of a bad boy die to his Mohawk mane). Even though he is a bad boy, he does have a soft side towards Fluttershy and Rumble.
 
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