In my experience, you really SHOULD worry about ur bike getting stolen. Living in brooklyn myself, having ur bike stolen is really not uncommon. My torelli was stolen about 6 month ago. Now my beater's a kilo tt for commuting (~12mi/day). Which is part of the reason why most of the components on my kilo is still stock. I just don't want to put too much into it. But in the end, what bike you lock outside is up to you. I'm just throwing it out there as a fellow brooklyn-er who got her bike stolen before.

I am currently piecing together another more expensive bike. But I would never EVER lock that one on the street. Basically what i'm saying is, you can keep ur current bike for running to bars, and also get another (better) bike for when u want to do longer rides that doesn't require locking up.