We ended up with a 4:1 mainsheet setup run through a cabin top double clutch that's shared with the main halyard. It's worked well for us both on heavier air days and (far mor common to us in the Puget Sound) light air days. The biggest factor we found was the friction in the blocks. Replacing old warn out blocks, including the deck organizer, with new ball bearing blocks made a much more noticeable difference than 5:1 vs 4:1. I posted about it here:
ericsonyachts.org
I later purchased blocks to bring it back to the original 5:1, but after using this set up for a few years, I'm going to stick with the 4:1
Block Comparison
We're replacing a lot of the running rigging this year. I'm not sure if the blocks I'm replacing are original, but they look old enough to be a possibility. Either way, they are old. All of them have small cracks in the sheaves, there's corrosion on the aluminum cheeks where the steel pins...
I later purchased blocks to bring it back to the original 5:1, but after using this set up for a few years, I'm going to stick with the 4:1