The issue is not premade vs pug. It's skill, coordination, and willingness to learn from one's mistakes, vs coddling.
At any rate, a public announcement to both sides about ragequitters, a 30 minute Deserter Debuff (15 minutes is not long enough to punish someone, and if they had to leave for legit reasons well they probably need the time off anyway), -Social Points (even resulting in the loss of Social Level if it empties out), maybe even -50k credits to pay for their space taxi.
I would be on board for ALL of these going into effect simultaneously. And anything else people suggest.
I have never quit a single warzone, disconnects notwithstanding and I hate people who quit--but I think what you suggest might be a bit harsh. Some people do not intentionally quit. Perhaps a 20 minute debuff of all expertise on the player who willfully quit? This way people who disconnect will simply have to find something else to do for 20 minutes and people who intentionally quit CAN still re-queue, but will be at a sever disadvantage in pvp.