BSLabs is pretty slow. I nearly always get same night results from Lab One. I drop samples off in person, though.
I've only ever seen slow results at Blackstone when someone is using the free mailing. Like your results with Lab One, I have always received same-day results from Blackstone (I drop off tonight after business hours in the drop box, when I get home from work tomorrow the results are in my email waiting for me to digest). TestOil, while delivering a great report, has always been two business days after known delivery of the sample to their lab.
Therefore, I posit that any real delays in the majority of oil labs' processing is mainly due to your (or the lab's) choice of mail carrier. The determining factor for me is focus and relativity: Blackstone is a mainly passenger-vehicle driven customer base and therefore has oodles and oodles of data to paint a perspective picture for your vehicle and oil choices and their suitability; nearly all other oil labs present your data "in a vacuum" in that they only look at your sample vs. its virgin data, and do not trend based on vehicle, engine, etc etc... and therefore leave more of the interpretation to you.
I do agree that Blackstone could really corner the market by streamlining their process and reducing the additional cost of some of the tests; when Wix/NAPA can provide 90% of the same data for 33% of the cost, it makes one wonder why there is such a premium. In other words, if you can interpret your own UOA, there is little to dissuade you from using a $9-11 test from Wix/NAPA with TBN vs. a $38 test from Blackstone or the nearly $50 test from TestOil, with most other oil labs falling somewhere in between the Wix/NAPA and Blackstone costs and essentially the same sample data.
However, since Blackstone reports universal averages right with your results AND is very willing to share the anonymous data for your vehicle that goes into their database, obviously part of their costs are associated with a higher level of personalized attention. But IMHO, if you're not exceeding your OLM/OM recommended OCI by at least 50% (i.e. 15k OCI on a 10k OLM) you're almost assuredly just throwing money away. OP, remember that a VOA only serves as a reference point, and the UOA simply tells you if the oil was suitable for your OCI... UOAs are not designed to or capable of determining "what oil is best for my engine".