I play alone as my hours are irregular and meeting up with folks is tough to swing. I've been in CZ, NAV, RES, etc.
I fight when the odds are in my favour and run when they are not. I make sure I have decent shields, engines, chaff, point defense and SCB's. I traded on my first account almost exclusively and killed a lot of NPC pirates who interdicted me with my weak weapons. Security usually turned up in time and helped me kill them. I took damage to be sure, but I lived. Today with the AI improvements, I run a lot more. I died from CMDR encounters due to inexperience.
A T-9 can carry a lot of defensive equipment and can get away from anything if flown intelligently taking the conditions into account. If you choose to fight, make sure you set conditions in your mind when to run, % hull damage, etc. When those conditions are met you hoof it and don't look back.