Oh, yeah sure, it most definitely covers a lot where it really counts, but so does my third-party coverage from a company my mechanic swears by but I never heard of. I needed a warranty, paid my $1300 and I signed the papers.
But every item you mention is covered under the BMW Certified Pre-owned program; the comparison is just so glaring, and I feel bad and annoyed on your behalf.
These are MERCEDES-BENZ cars, I thought that meant something more and better, but maybe not anymore, eh? One would thing they would be trying to maintain a standard, but silly me...
My point is that based on what you have revealed, one would do just as well to go to a reputable independent, of which there are now plenty all over the country, who can offer the same used and comprehensively inspected inventory as any dealer, offer legitimate third party coverage, and all for much less than any dealer.