We think it's really great that the new membership system gives paid members badges next to their names!
Is there a way to award additional badges for accomplishments or Political Capital?
There aren't any plans to add badges like you describe them. The control panel lists "honors" which are based on whatever leaderboards you have set up. So this person is the #3 biggest earner of pc this week, or #1 biggest commenter this month, that sort of thing. Those aren't exposed publicly though at this point.
Never mind how that would be counted – our question/request is simply if nationbuilder has planned any badges functionality. We are planning to award foursquare style badges “by hand” for a project.