We get .stp files of PCBs from a vendor that causes Solidworks to slow down a lot. Opening larger assemblies can take beyond 10mins.

After numrous attempts at speeding up the workflow, we're looking for a way reduce the complexity of the model. As of now a PCB model may have 300-500 imported features. Most of these are small SMD components and traces that have no mechanical use. Does anyone have a good workflow for improving this situation?
stepstpImport exportperformance