The path for the file that contains the reference should usually identify the product, and for content from Daz (and isntalled with its metadata) you can also use http://docs.daz3d.com/doku.php/public/software/dazstudio/4/referenceguide/scripting/api_reference/samples/metadata/list_products_used/start to generate a list of products used, so aply one of the "problem" morphs. You cana lso, with a little adjustment, use this for content from other stores that has been set up (by the vendor or by you) as a product.

It isn't large content sets alone that cause the slow down - it's large libraries of morphs for a given figure as all these links have to be cross-checked on loading to get everything correctly hooked up.