Favorite:
PURPLE. Lead to people discussing some lesser known characters, brought some much-needed levity at the right time and didn't overstay its welcome that much. Sure, it was a miscalculation in the end, but thank you
epicmartin7 for starting that.
Least favorite: Cacomallow because it wouldn't die ever. But it's been talked about enough, so a runner up would be how Sabi, Fatman and Verg hyped up several extremely vague leaks when the whole shebangs were threadbare at best.
As for my very personal ordering of favorite DLC characters. Note that I do not dislike any character:
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