Pretty cool, I'll be downloading most of this stuff but I feel I must make a small amend reguarding what you point out as official, unofficial and experimental warbands.

All warbands that are from a town cryer are official! Now they are add ons and no one has to accept them into any campaign, but they are pretty much official and balanced (well, as balanced as they would ever be, considering skaven came out withthe original rules and is the most broken OP warband anyway).