OK, well I'm surprised that you buy stronger ARB's and use the lesser rear setting which admittedly is 50% stiffer than OEM, however the stiffer setting gives a little more at 65%.
So if you use the slightly softer setting on the rear ARB, it allows more flexing at the rear and the front wheels do not have to do as much work to get round the corner....., but if you use the stiffer setting, it can cause the front to work harder and understeer on cornering..... unless you use the ackerman setup principle of slightly toeing out the front.... then you have a go kart effect on cornering, goes round on rails!!
Anyway all personal preferences, just have fun with the setup.

Ebony Black Avant with Black Optics, Silver Leather and Piano Black/ Full Milltek - 100 CPSI cats and non-resonated! TVR for the summer..... and SL55 AMG just for the pose!!