Indeed. In v2.6, a hierarchical projection of multiple fetches to custom classes will be added, so you can fetch customers, orders, orderdetails for example in 3 queries (using Linq, or a prefetch path) and project each set onto custom classes.
The biggest hurdle is merging the sets. The raw logic is already implemented for prefetch paths, it's just that it's not available in such a form that you can use it for other code than prefetch paths.
To project the object graph onto sets per type can be done on custom classes, though it requires some manual code. The meat is already done for you, so it's rather easy. What you should call first is ObjectGraphUtils.ProduceCollectionsPerTypeFromGraph(collection), to get a dictionary with per type the entities in a collection. From there, you can project each collection onto custom classes using your own projection code. For the fine print, see EntityCollectionBase2.CreateHierarchicalProjection()'s code for ideas.