You need to fix geometry as well. You probably would benefit from stiffer springs. Are you maxed out on preload? My rear is raised and front is lowered compared to stockIntermediate Rider Here.
Stock 13 ZX6R.
I've set up the suspension to text book sag, then made some rebound/preload adjustments based on what I was feeling while out on track. Overall I'm satisfied with the bike.
However, I am a heavier rider (230-235 No Gear). I notice the front end getting light frequently, especially corner exit which causes understeer and lowers my confidence.
I'm interested in hearing opinion on only re-springing the front and rear to better suit my weight.
Side note: I'm signing up for YCRS in 2020 which I know will help.