Mainly because while I can handle everyone with little to no problems, Narikos combos take forever, and she usually ends up getting me killed. "Mash square as fast as you can! Who cares if Sly is running at us with a level 1 or Kratos for that matter. Gotta keep mashing that square!"
Sackboy... In FFA because I know the other two players will do nothing about him sitting in the corner, and just go for each other.
I go for Sackboy for most of the match, but I don't put too much focus into it, rather not fall for his traps. It's also pretty easy to tell when a Sackboy is setting up for his Level 1 & 2 Supers.