It is possible, that Satoshi is/are reading all these bitcointalk contributions ... and although some pepole want him/her/them to come back, nothing happened.
Tell one good reason why Satoshi should come back. (good reason = improvement of Bitcoin)
I don't see any good reason for Satoshi to come back. The bitcoin source code can be updated by anyone which then needs to score 95% confidence from the miners to get updated to the source code. So Satoshi can do it even after staying anonymous. But yes, if Satoshi comes back and then make the changes then it will be easier to win miner's confidence.
I would say, Satoshi must stay anonymous for the rest of his life! I strongly feel that these lawsuit of Craig Wright is a staged incident by FBI to lure Satoshi out. Because obviously Craig doesn't have access to Satoshi's stash of bitcoins.