The Spirit Realm

If you've got the portals quests done, there is a super duper easy peasy task for faction raising. Speak to Archarcanist Pintanus in the main building and say "more" to get it (I forget exactly what the name is). Head to Silyssar (non instanced version) and kill five rock piles, which can be done without aggroing any mobs at all, and gate back to Pintanus (make sure you bind there first). The piles respawn every 6 minutes and you get 100 plat and a faction increase every time. I went from kindly to ally in about 20 runs, which took a little over two hours.

Amiable is the biggest faction band, I believe. Once I got to kindly, warmly then ally seemed to come quicker.

From what guildies have told me, since I'm not there yet, your looking at 2500 orux for ally, or very near that.