I think that separate BOMs coming from different zones is a great thing to have.
We will maintain an official, vendor neutral BOM. Pointing to a particular provider is kind of making publicity, and we don't want to do that. Unless of course a particular vendor is interested on sponsoring the project. Other, more specific BOMs will be published alongside with it on the documentation as contributed ones.
On the other hand, since you are taking the time to look for substitutes, there's no reason not to include them on the official BOM. That information would certainly help people trying to build the system. Unless, as @HalloweenBob said, they fail to give a working board when built. But for the passive components that improbable.
Here's an editable version of the BOM. Could you please include there a mention to the alternative components where applicable? If you do please post the new version here, and increment the number on the file by one.
Thanks to Both for your contributions!