Ember index data -vs- show data

How do people deal with index data (the data usually shown on index pages, like a customer list) -vs- the model detail data?

When somebody goes to the customer/index route -- they only need access to a small subset of the full customer resource. Since I am dealing with legacy data, my customer model has > 10 relationships. It seems wasteful to have the api return a complete and full customer representation for every customer just to render a list/select/index view.

I know those relationships are somewhat lazy-loaded, but it still takes effort on the backend to pull all those relationships in. For some relationships (such as customer->invoices) this could be a large list of ids.