Like Susie, I use a 3:1 water:lye ratio to make my liquid soap paste. Stated another way, that is a 25% lye concentration. Like Nikos, I prefer to use lye concentration, not "water as % of oils".
I've used as low as 2:1 ratio (33% lye concentration) to make the paste, but I regretted doing that -- the paste is so dry and more difficult to work with.