Ah ha! This is exactly the kind of thing we need - a no-brainer setup. Heck, there's even a little business here for someone: sell computers pre-configured for mining that boot right into it. If they were done properly, we could and should recommend them on the website.

By "properly" I would mean that they ideally don't require much setup beyond simply plugging into the wall, switching on, and plugging mining hardware in. So, self configuring. The base OS should be minimal (good to avoid the machine getting hacked), and ideally it'd have a way to with user confirmation upgrade the software components automatically. For instance, when a new Bitcoin Core or a new P2Pool is out, the screen should display information about what the upgrade changes and require the user to explicitly accept (i.e. not auto-driven by the seller of the machine).

I think the arguments about whether P2Pool will be competitive in future can be put to one side for now. It's all rather speculative and one thing we can be sure of, if it doesn't grow and become easier/more popular the details of network propagation in future won't matter  - nobody will be using it anyway! There's a step one and a step two here