In cases when you need to fetch collections eagerly within application code but none of these collections are indexed, it would save a lot of indexing time if only columns and collections needed for indexing were fetched.

In my case, indexing 530 000 entities consisting of 40 columns and 7 collections, it takes around 1 hour to index when collections are eagerly fetched, but only 3 minutes if collections are not fetched.

If it was possible to only fetch needed columns and collections the build index performance would improve a lot in these specific cases.