3. I've personally wondered if he left around when asics came out, the point of no return if you will. Asics essentially centralized BTC in a way , starting with suppliers in particular , bitmain. Lately I've felt the only clear winners in BTC are the guys that where in early or asic sellers. I personally don't think that was Satoshi's vision. What good is a decentralized currency if majority of it's owned by the elites already?
Asics were not yet out when Satoshi left but since the first GPU miner everyone should have seen the writings on the wall, it was clear that if the reward will prove to be enough incentive miners designed for this would appear, and they did so as early FPGA.
As for his own vision on decentralization, it puzzles me sometimes, he once talked about a
gentleman's agreement when it comes to the hashrate race to have coins distributed equally but at the same time he
talked about server node farms to take the burden of the network.
I think that he knew there was never going to be some sort of democracy in this and in the long run the ones affording better gear will prevail, even with CPU mining the threat as there.
Besides, he had some other ideas too, with which not so many will agree these days:
New users wouldn't really even need the Bitcoin software. They could download a miner, create an account on mtgox or mybitcoin, enter their deposit address into the miner and point it at anyone's pool server. When the miner says it found something, a while later a few coins show up in their account.