Those already using P2Pool are not necessarily those best suited to suggesting enhancements. The most useful opinions might be from those, like zimmah, who currently use GHash and
don't want to switch. They are the target, right?
I'm especially interested in the opinion of larger stakeholders on this matter, i.e. those who hold large positions in BTC. The speculation forum seemed like a good place to get a reaction from them, only, so far nobody picked up that invitation.
Define "large position" 
I think the really big holders are too busy sitting in their castles to comment or fund something important like this... pffft, most people are just mindless speculators with little care or understanding of the underlying technology. Tragedy of the commons and all that.
/pessimismDon't really want to force anyone here to reveal his net worth, it's a tricky subject. So I understand it's better done in a don't ask, don't tell manner, but like I wrote above, I know from the discussions in here that there's a decent number of 100+ BTC holders on this forum, which is what I'd call a large(ish) BTC position, agreed?
But in the end, it doesn't really matter how many coins you have, the idea would be that if you have a stake in it, you should be motivated out of rational self interest to keep the network decentralized (as much as possible at least). Donating, say, around 0.1% of your BTC worth to a cause like this seems reasonable to me.
So, say if you're sitting on around 100 coins, that means donating 0.1 coins. At a total of around 1000, 1 coin. I'd expect we could get a pretty decent amount of donations together like that, if people are convinced it's a worthy cause.