Memcoin in specific proposed something like adding democratic processes into the coin itself. I think that would be the best way to improve the protocol. The next coin should probably include democracy and voting within the coin itself so that holders can somehow vote as a group.
It's an interesting proposal, though. Reminds me of "BIP" 2112's proposal to generalize the current "Version"/"P2SH coinbase" mechanisms by embedding the block validation code in the blockchain itself, and letting miners indicate which such algorithms they're willing to endorse.
The Decrits proposal (see sig), among many other fixes for bitcoin's problems, has a section on voting. It was at the very early stages in that document, but I have refined it quite a bit. I think the idea of voting as part of the protocol may be so different that it is shocking to some, but I think it is necessary to avoid the control that the developers would have over the protocol (and perhaps the influence that an exchange, for example, might have over them). Voting power is not determined by held currency or hashpower (though having currency invested is a requirement), but by the people who have provided beneficial and continued service to the network via transferring and validating transactions. Even if there is an Evil Network Takeover (which will take time and lots of money), the network will have the opportunity to split, and the guys on the wrong side will not be allowed to transfer their money to the honest side of the split.