Well the title is kind of descrptive enough I think XD list what pair/pairs you think would be the best, or Worst combinations.
Like um, for example - I think Mikan could work very well with Laala and Leona. But I think she would need someone who could help her a bit more by being a little strict, like maybe Mirei
In terms of worst case scenerios... I don't really see Aroma and Shion being able to work entirely well together. I could be wrong, because they are both very strong-minded girls, but that is also why I think they would struggle, too.
Um... well that's it for me I suppose XD Please try to be descriptive with your answers, and please don't user favortism. This is just a fun, random pairs/coupling topic.