In a sence Laowai you're right. "Do unto others..." is a pretty good motto. Be it in weapons loadout, pvp arrangements, refrianing from powergaming type RP.
A lot of roleplay uses PVP as a tool. Sirius is largely at war, which provides a lot of scope for plotlines and interest, and also gives people the scope to blow each other up.
Now this does seem like the roleplay empahsis kinda rules out the fair play aspect, but infact it does. You don't win at roleplay by attacking people with overwhealming force. You win at being a jerk instead. Roleplay your characters on the server, have fun, but not at the expence of anyone else's fun.
As I said in my earlier post. There are plenty of way of roleplaying your way into sitting out an unbalanced fight, which while requiring you to think on your feet a little, can both add RP depth and balance a fight out... Best of both worlds anyone?