As with most things in EVE, being in nullsec yields more profits. The planets in nullsec and WH space seem to produce more products than HighSec.
Truth be told, the Planetary Interaction isn't going to make you rich overnight, infact, all we using it for currently is to product POS fuels. So that saves us a little bit of ISK. The main game hasn't changed that much at all with PI stuff.
I would suggest you join a corp like EVE University that will teach you the basics of "corp life". Most nullsec corps happily accept EVE university guys. Once you in nullsec, the game of EVE evolves. I currently run a trade route from HighSec to nullSec and I am making a killing ;)
The game really opens up in NullSec so try it out.