Originally Posted by blue_neon
The main factor is your weight aswell. Since you are riding all differen't types of terrain its harder to get 'one' good tyre pressure.
A lower tyre pressure will provdie more grip, but may slow you down. A higher tyre pressure will make you roll a lot faster but may not grip aswell.
If your not going to be doing any jumping or such then a lower tyre pressure sounds good, but like LowCel said, just experiment. Start running 40PSI, then your next ride run 35PSI, then 30PSI, then 25PSI. Pick the one that feels the best for your set up.
I'll also add to this long post by giving an example of how i've changed my tyre pressure's with different tyres. I had Panaracers Fire XC 2.1" and i needed to run low pressure of 30PSI. I then bought Kenda Nevegals 2.1" and i'm happily running 40PSI with the same traction on corners. There are many variables.
As everybody says trial and error. But seeing how low you were with your Panaracer's, and the new tire/tube set-up I'm getting, I'll probably start at 30psi. My main concern is traction especially in corners that are almost all covered in pebbles and small rocks. I've really been nervous, especially on the downhill corners and straights with the same cover.