He's our best swiss-army knife. He's playing on the Kadri line because Babcock trusts Brown's defensive abilities and that line is going to be getting tough matchups. Brown doesn't create a whole lot of offense, but we really don't need every single player in the top9 to be a 30g threat. With so much firepower I think many people lose sight of the fact that 20g production is a 2nd liner on a lot of teams. Brown is an excellent bottom sixer and having to play him on the fourth line some nights is probably the best indicator there is of this team's elite forward depth.
Kapanen seems to be just as good defensively as brown, and I think (only my opinion) Kapanen has a higher offensive ceiling