Without the filter (or some other possbile approaches), the file contents are not accessed. I would not insert all acs_objects into the queue: for some content it makes sense to index based on the item_id, for others based on the revision_id (both are acs_objects). notice, that also user_ids or package ids are acs_objects, so the indexer won't be able to do anything with this. maybe insert everything into the queue does not hurt, but i certainly would not do this for testing on a system with some content.
try to understand, what the FtsContentProvider service contract is about, and how the datasource works (again, you might check our xowiki, or various other packages)