And his relationship with Jake was fantastic, and everything that Wesley and Beverly (who appeared to be complete strangers) should have been. "The Visitor" still chokes me up.
Sisko's best scenes are with Jake. I think Cirroc Lofton brings them both up a notch. Separate they both have issues with their characters (Jake mostly to being useless, and Sisko is just angry and unstable)
In defence of Beverly and Wesley, I think it was implied that since the death of Jack, both Beverly and Wesley have become distant with each other, due to the trauma both of them being a reminder of their loved one (Father and Husband respectively). Perhaps due to the fact that Wesley, being a guy, did not know how to relate to his mother as well as he did to his father.
Jake and Sisko are both men, so easier to relate on that level. I wonder how it would have been if Jake had been female, or Sisko had been female.