I did 100% and my soap wound up awful. I just did 60% and it was perfect for me. I am using an extra I made (it's a week old lol) for hand washing, and it's awesome. I don't wait. I use one extra immediately every batch and watch the changes over time. Most soaps mature best at the 8 week mark I find for me. 4 weeks is fairly mediocre, and 6 is a false positive for at 8 it becomes awesome.
Salt I'm expecting even longer curing based on what I've read, that and my crummy 100% salt that had thin scant lather can now work up a lather if I work it in the warm water for 30-45 good seconds...and it's around 5 months old or so now.
Remember, if decrease the salt you decrease the co a tad and this can decrease the sf a tad. It is a juggling act between salt, co, and sf with the extras bringing up the rear.