Well I'd voted for keeping it as-is before learning that hopping-pools are actually causing undue stress on the system and/or operators. Unfortunately you can't go back and change a vote, so please disregard one of the proportional votes. I think the best way to choose is to compare and contrast what the various methods actually mean to the pool and its members.
DGM - I haven't gone and looked up how the calculation is actually done, but on the surface it sounds a bit complicated. The pool absorbing some of the fee from shorter rounds and paying it out on the longer rounds seems to add a bit of accounting overhead. I would think there'd be risk of pool members accusing the pool of trickery if they don't understand precisely how it works. Unfounded negative publicity would be a very bad thing considering how paranoid some bitcoin users are to begin with. Wouldn't this also expose the pool to risk that a large number of subsequent long rounds causing the pool to constantly pay out without any income to compensate for it? Long term this should average out, but the pool would need enough capital to survive shorter-term ruts.
PPLNS - This is a very transparent methodology, and is simple to calculate. The negative here is the shares become completely worthless over time. I think many users that only mine part-time (not hoppers, but those that mine when not gaming, etc...) would tend to not like this method for the same reason hoppers don't. This is a non-issue for those of us who mine 24/7 since we're constantly replacing the shares that roll off with new shares.
PPS - I wouldn't even consider this for the pool. Right now BitLC is built on being a fair pool, not charging fees to the miners, and being open and transparent. Switching to PPS would cause undue risk to you as the pool operator, and/or would require the pool to charge fees. The first is not fair to you, and the second goes against the philosophy of the pool (at least how I perceive it as a pool member.)
Score - This may be the best choice, since it eliminates the "worthless" share issue with PPLNS. A part-time miner still gets "something" if they stop mining during a round. It would ease their minds getting a miniscule "token" amount for the work put in. Hoppers would still get paid some too, but they're in it for the quick reward and the token payment they receive should not be enough to have them view this pool as a valid target.
For full-time 24/7 miners the payout method really means nothing in the long haul; it all averages out. The change in payout method needs to be used as a method to attract part-time individual miners that come and go based on individual PC habits, but not give enough advantage to make it a viable pool for hopping purposes. Score-based payout is probably a good balance and would be my first choice, but if you wanted to follow the KISS principal, PPLNS is the way to go, and I'd consider that my second choice.
No matter what you decide, thank you Jim for all of the hard work you put into running the pool. I know it isn't easy, and to do what you do without charging fees is saying a lot.
Jeremy