Were you using Reverse Node Reference? Now in Drupal 7, you have reverse references available to you in views:
So you can use those relationships to go and load other content from one base content type (e.g. list blog posts or other products that reference this node or product).
Ideally, though, you might use EVA or or Views Field View to attach a view to an entity via a field. That view would use a base of whatever type of content or entity you were wanting to display, and then you'd just a contextual filter to limit it based on the field that references it.
Secondly, Commerce Kickstart doesn't use Solr out of the box, but it does use Search API. You can use Search API with Solr but faceted search and regular search do not require Solr. You can have Solr index entityreference fields and Views can use them, but all that does is change which checkbox you select in your Views config and not how you actually create the View.