Flashgunner's Guide of Farming.
You may know, farming is a fast way to get XP.
So here's my guide.
Levels 1-5 Dynastar level 2.
Levels 6-8 Red Sun level 4.
Levels 9-14 Cycorp Level 5 (Bring a buddy and stand behind the one burning plant, have your buddy go kill the vular.) (recommended level for buddy: 25+)
Levels 15-19 Delta-7 Level 1. (Do not go for the assassin)
Levels 20-25 Numa Prime level 1 (stop at 1 remaining)
Levels 26-29 Slouch-O level 3
Levels 30-37 UC Shipyard level 2 (stop at 26)
Levels 38-41 Voleria Inner Core (stop at Operative door)
Levels 42-46 The Scorn Crusade level 4.
And that is my guide, if anything is left out, let me know.