Domains have been done already.
Not like this they haven't. I3 has the potential to be the first to build a decentralized namespace that actually has widespread adoptation.
Once BitShares X is out and stable... we will probably implement BitShares DNS simply because it would take me about 2 to 3 days to implement the blockchain aspects of it. Everything else can be left to the community.
After that BitShares Me is a stepping stone to BitShares Music so must be done first. The blockchain for BitShares Me is also only a couple of weeks of changes on top of BTS X.
BitShares Bingo probably something best left for a 3rd party as gambling has negative connotations... at the very least we need a track record of delivering solid real-life apps before getting into the gaming business.
The one DAC that I think is as big or bigger than BitShares X is the new Insurance DAC which I just posted about and will be releasing a video about. It will probably be developed over the course of the next 12 after BTS X.