I'd always suggest running at the manufacturer's spec regardless of feel. Especially with dual compound tyres.
With pressures too low, you'll wear the soft sides quickly during general riding, too hard and the soft sides won't engage with the tarmac, especially on the front during straight line braking. It's how they're designed to work. No?!
If you want to consider your weight, if your 80 or 100kg on a 200kg bike the total weight variation is 290kg +/- 10kg, (about 3.4%) If you consider that significant, you would also change your tyre pressures every time you add 15kg of fuel to the tank. Perhaps If you put on 40kg of luggage or a 80kg pillion, then it might be worth thinking about.
Just my 2 cents. I recently put one of those dodgey little compressors under my seat and bought a digital pressure gauge, so have been giving it a bit of thought. I'm 105kg and running at the pressures recommended on the sidewall. :-)