I'm not sure that last statement about being higher payout than Eligius is accurate. You can put 0% donation into both, both pay transaction fees, and Eligius pays merged mining on NMC. Yes you can merge mine in p2pool, but you are solo merged mining, which is almost the same as solo mining BTC.
I did not claim it has a higher payout. I claimed it has a higher expected value (a mathematical term similar to average) over a finite period of time (more precisely a finite number of shares). In fact they have the same expected value over an infinite time horizon, as far as I can tell.
And when you throw in increasing variance with p2pool, I definitely think Eligius comes out ahead (which is why I'm there, not on p2pool).
I agree eligius most certainly has lower variance and may be preferable for that reason. This is a different question than expected value in finite time.
There are other pools that also have higher expected value than eligius in finite time but also have lower variance (certainly much lower than p2pool and possibly lower than eligius though this is certainly not clear). It isn't my intent here to promote any particular pool so I won't name names. I'm just pointing out some differences in payout methods that may or may not matter to a particular miner.
BTW, solo mining has the exact same expected value as mining on a zero fee hop-proof pool. But obviously very different variance.