I guess they told you that the bumper was PVC and not fiberglass. Cracks were in the paint or was the plastic broken? I had one bumper plastic welded to fix a crack and they also plastic welded the gouges in the bottom of the bumper rather than using bondo.

Before the paint would have been a great time to install the Roe Racing front fascia scoop and improve aerodynamics and cooling for your GTS. Unfortunately the chin spoiler seems to act as a Gurney Flap under the car increasing the lift of the nose and creating positive pressure behind the radiator causing slower airflow through the rad. If you look under a Gen 3 you'll see there is no chin spoiler and the RR streamlining aero panel behind the front bumper to the oil pan.