Not gonna happen. All previous VH’s had one single action skill. In BL 3 they each have three. In order to make a BL 3 version of Axton, he would need two additional action skills. Randy Pitchford is on record as saying “there is nothing left in the tank…we put everything we had into these four vault hunters.” (Paraphrasing the second part, the first part is a direct quote).
You couldn’t play any BL1 characters. Three are NPCs in BL3 and one is dead.
You couldn’t play Zero or Maya for the same reasons.
You couldn’t play Timothy, Claptrap, Aurelia, Wilhem or Nisha. NPCs in this game or dead.
That leaves: Axton, Sal, Kreig, Gaige and Athena. Personally, I would take a fourth skill tree on Flak, Zane or Moze over any of those characters. Four of the above I never even played because I wasn’t interested. If I wasn’t then, I won’t be now.
And regarding the “current lack of build variety”. I wholeheartedly disagree. I actually have two completely different Flak’s: Gamma Burst and Crit. Each with different skills and wildly different gear. Same for Moze: A Bottomless Mags/Bloodletter and a Splash Blastmaster. I change my Zane back and forth all the time and he has a dedicated mule with anointed gear for the action skill I’m not currently using.
How many different Sal builds were there in BL2? Maya? Maybe a different COM and a few skill point changes, but nothing earth shattering. Zero was the most diverse, between melee and sniper. If you played TPS solo, you could ignore one of Aurelia’s entire skill trees.
Given the state of the game, I just assume focus on two things: fix the the stuff that has been broken for a while, and keep focused on DLCs 2, 3 and 4 because Moxxi’s Heist is awesome. One of the best in the franchise.