Welcome. I've got an 05 2.3L as well. I know what you're talking about with the rough shift from first to second. Except I don't know if I would really call it rough. When the car has been sitting overnight, I notice a bit of what I would call lag shifting from first to second whether in manual or automatic. It just seems to take a moment or two longer to decide to actually shift from first to second when in automatic (at least, a moment or two later than it would normally shift on a warmed up car), and it takes a moment or two longer to shift from first to second after shifting in manual mode. I've never had any problems come from it, and I've had my car serviced multiple times and they've always checked the trans fluid.