Eyeballing it is useless. You can take a tape measure and go from front to back at the same point in a straight line and mark it with a grease pen or permanent marker. Put it back on the car and see if it is rotating straight or if it's twisted. The only way to check the driveshaft is still balanced is to have a driveshaft shop check it.
Tire vibration due to imbalance normally is within 50-60 mph. Unless you recently hit a curb , threw some weights off or the tires are wearing uneven, I doubt that'sthe culprit.
Small possibility -I'd check the wheel bearings and ball joints. Jack up the car and see if you can wiggle the front tires side to side with your hands on the tire at 3 and 9 oclock-to test the wheel bearings. If you can wiggle it with your hands on 6 and 12 then its the ball joint.