Although your forks are different, my KX450f forks were
intolerable for woods riding so I modified the shim stack by
removing 7 of the largest shims.
Very noticeable improvement as it took a lot of the harshness
out of the ride although I still may take a few more out when I
do the fork oil the next time.
I did do gold valves on my KDX and Race Tech does supply
shim charting based on your weight and riding style which
takes a good amount of the guess work out of the picture.
Here's a pic from the removed stack on the KX.