1) Yes. 1& 2) In fact the C-instance messages do not conflict with each other and gets accepted immediately. These messages do not even need a ballotnum, but t

1) Yes. 1& 2) In fact the C-instance messages do not conflict with each other and gets accepted immediately. These messages do not even need a ballotnum, but the ballotnum used is that of the O-instance to denote sort of an epoch of which sequencer the sender thinks is still in-charge. 3) If replication messages are large, you can just order the "commands" referring/pointing to them via Paxos, and not necessarily the data itself.