I like it. There are plenty of negative actions that you can take such as Tbaggin and body mutilations but no way to pull off something positive.  Not sure about B for high five because of accidental melees. The D-pad would be better no?  How about a bow? In MMOs it is common to bow to show courtesy or thanks. So instead of a Tbaggin a guy we can bow to show that it was a good fight. 