I don't know if this has been brought up before or not, but these long gaps between blocks are likely to get more frequent i would think unless the pool grows rapidly enough to keep up with the increasing difficulty. Given that possibility, would it be possible to look at paying out the fees every ten shifts or so? That way we get a little bit back every now and then no matter what. I honestly have no clue what that would amount to.
The problem is, with PPLNSG, only the LAST 10 shifts get paid...so in this case the many shifts which were completed before the last 10 will receive nothing in exchange for their work. The only way to provide a payment to EVERYONE is to treat this like a completely different pool, which I don't believe is the goal. Many people are here because they prefer the PPLNSG Format, and in addition, believe in supporting smaller pools so that we remain decentralized. If more users come, then of course we will theoretically find blocks faster, but users will receive less BTC for their share due to having to spread the love to all the workers.
I guess I might be misunderstanding your question or thought, but it sounds like you are looking for more of a PPS pool which pays you per share no matter the luck of the pool. The biggest downside to these other than the obvious centralization issue, would be the higher fees that are charged to maintain that type of pool. Pool operators of PPS must pay the reward per share and to cover the times of bad luck, they charge higher fees. It's just the nature of the beast.