Rob: besides the reduced harshness, did you get a sense the bike was turning in more slowly after the preload was reduced? <snipped>
The best answer is can give is that the front was after adjustment, now it's had accurate handling alignment with the rear. Sag was not measured for demo ride of course, but the seat of the pants meter said OK'. Meaning, through a curve it was neutral on acceleration or braking.
That's what is wanted by me, you don't want either end trying to pass the other in a curve, do you?
This 750 is the first Suzuki bike that I have ridden that needed less rear preload. Normally the front is quite stiff enough for me, and if I increase the rear preload up a notch, the ride handling over bumps and cornering feels great, gets too touchy.
In this, I mean I have to concentrate all the time, as it will steer very quickly - blink and your off the road quick.
A half a notch up on the rear is what was wanted most times and I would dismantle the rear shock and add shim's.
To increase stock fork preload to match the overfirm rear, may work for some, but not in your suggest weight range unless track days are your want.
An over adjusted front preload can be dangerous when braking hard downhill on a curve with soft OEM springs, the front tends to wash out unexpectedly like in MOTOGP. Good one minute, wrecked the next.
Just go down a notch on the rear and you will have a good bike.
People here around 65KG had said the 1000 has far too firm a front end and a softer rear, so Suzuki gave you the opposite; so you won't get the problem of the EFI 'snatchy throttle' experience over bumps. Swings and balances, heh?