I have two Warlocks (32 and 31, with the second one almost 32) and I am leveling up a TItan. I tried the Hunter, but it really wasn't for me. I would not dream of deleting either of my Warlocks. It's by far my favorite class to play and it's really nice having a back-up to use for those terrible RNG days. I actually made the second Warlock for VOG where after over 25 runs, the gauntlets for my main Warlock refused to drop. Due to the terrible RNG system, I needed a backup to get my main Warlock to 30.
Now CE is supposed to be better in that area, but I still kept my second Warlock around. It pretty much assured me that one of my Warlocks would be 32 by the time CE Hard Mode drops, and well, mission accomplished. if you play a ton, none of this probay matters as all of your 3 characters SHOULD be 32 by the time CE Hard Mode drops, but I do not play that much and didn't want to take the chance. Giving this RNG system, I'm keeping my 2 Warlocks.