I think people should leave the Watchtower on whatever terms suit them (the people leaving not the WTBS).
Wife and I DA'd almost a year after we stopped JW related activity. Both of us were converts, I had no JW relatives, wife only had two and we didn't see them very often. Both of us wanted to be on record as leaving because we didn't believe in what they taught, nor did we accept them as having any authority in our lives.
We told them we knew they would make an announcement. They could say we'd left, if we found out they'd said anything else we'd take legal action (and I had a lawyer if we needed him). We also attached about thirty pages of research telling them why we would not accept their authority on anything.
It felt good.