Unfortunately, being on a PVP server allows people to get the open world pvp kill achievements. Therefore, people on the PVP servers will potentially have a higher AP count. It is possible to them on a PVE server but would require either boosting, which would truly suck to do, or try an motivate people to go pvp on certain planets on both sides. I really wish they had separated the PVP achievements from the "Locations" tab so i could have more then 6 100% planets.
I have no issues at all to 'convince' people to flag. Easiest way is to just go and invade the impie homebase. The turrets are easy to kill since bioware hasnt updated them to 55. You can pretty much solo the turrets and duo the humanoid guards. Most of the times you will have imps trying to help the guards by attacking you .... et voila ..... flagged impies are at your disposel.
Just to be clear .... I never ever forceflag people, thats low.
What I also do at times is when I see loads of flagged imps while levelling on my impalt is just relog to pub and go to the place where they were. Most of the time worldbosses are a good location to find flagged people (not sure what they are thinking to so up flagged on those fights, but I dont care, meat is meat).