Twi: prefers exotic weapons with assloads of elemental effects, the weirder the better. All Maliwan, all the time. Not sure about her skill tree.  
Rarity: She’d go for smaller, “ladylike” weapons, pistols, mainly. Skills would be  
Fluttershy: long-distance sniping from concealment would be her thing. Her skill tree would probably have “invisibility” and “camouflage” options, or would emphasize healing and party buffs.  
Applejack: Torgue and Jacobs weapons exclusively. Her playing style would be to select weapons that made the biggest, ugliest holes in things possible.  
Rainbow Dash: she might actually eschew weapons entirely in favor of physical melee combat.  
Pinkie Pie: She’s going to like colorful, loud explosions and anything funny or goofy. She’s going to have a skill tree that buffs her party cannon or summons alligators or something. She’d probably be the only one who could turn the Bane gun into a viable weapon.

This little pic popping up in my feed makes me want to play borderlands 2 again.
 
so many damn hours sunk into that game, I hardly even play it anymore.

To be fair, I know way more about the original Borderlands guns than the sequel. Especially since the sequel decided to be a diva and for no apparent reason, bluescreens my computer every time I try to play it or the pre-sequel since I got my Nvidia GEForce 950 installed. And only those two games, everything else runs fine.
 
I’m currently running a 12 round Desert Stomper, 12 round Desert Shotgun, a 51 round Hellfire and 6 round x4 Defiler on my second playthrough. It’s a goddamn good thing I’ve got a good Support Gunner mod (39% increased magazine size, sooo close to a full 200% mag) because The Destroyer takes a ludicrous amount of ammo to kill.

@Background Pony #8090  
“Dahl Sniper”  
“Drum Magazine”  
Son. I am disappoint.

“Oh, crap, is you Hyperion? I heard all of you are robots and you eat metal out of the garbage and stuff – knew you wired death machines would be coming for me once Roland went missing. If you’re here to kill me you should probably know… You’ll never take me alive, you robotic sumbitch!”

Hey, I remember this.
 

@Keith Mowz  
The body and barrel look like Dahl to me, although it does not contain the drum mag you would normally see with dahl snipers.
 
I must presume it is an aftermarket Etech.

Huh. What maker is that? The barrel looks Hyperion-y but their gradually stabilizing shots gimmick is complete and utter garbage for sniper rifles. (And most other guns too, IMO.)

Twilight is lock and loaded.

@TGM  
All I can think of is reskinning Maya’s phaselock.

@TGM  
To summon a Deathtrap resembling Spike.

I wonder what her action skill would be?