I have a similar one on my commute. I take the lane. I don't usually have trouble keeping up with the cars once the light turns green though, sometimes I get going too fast and have to slow down even.

At intersections where I can't safely get over to the left lane, i just ride through the intersection, stop at the pedestrian "push to cross street" button, then carefully walk my bike into the rightmost lane going the direction that I need to go. That way I don't have to walk across the street.