Is Geek Good Enough

So I spent last night with some friends, and we talked about my shirts. They've got...some ideas about things that I need to start focusing on. You know...branching out some more from the geeky stuff and into more punky things. Which is tempting, because I can make a good Clash joke as well as anybody, but then I wonder...should I just focus on building my brand among the geeks for now? Work on the Harry Potter and Doctor Who fans, eventually branch out into Battlestar Galactica and LOST, and see where I go from there? Or should I try to build the two lines at once, so that it's not as hard to switch gears?