+1 for trial & error
fwiw
I do like the front approx. 10psi lower than the rear
I'm about 223 lbs, then add clothes, a 20lb bike & a 5lb trunk so at about 250lbs I like my rear 25mm tire to be about 100psi, maybe 110 tops, but no higher. the charts say I should go higher but my trial & error has brought me to about 100 rear / 90 front