Advancements in either p2pool software or something similar would go a long way in starting to alleviate the problems associated with mining centralization. Unfortunately, there hasn't been enough incentive to advance these things. I think instead of removing mining from the reference client, it should have adopted and improved upon the p2pool software.
No, really, once you have a cartel of pools, which is unavoidable with a PoW type income lottery, the network topology doesn't really matter, in *reality* you have a server/client system, where the pools are the collective server of block chain because they
are the principal source of the data. The other nodes in the network are nothing else but proxy servers of this data and ultimately, the clients.
you still dont understand. if you think nodes only job is a data store. then please go read some code