After much making of spreadsheets and trying numbers, I decided that 10,000 kills outside Ratchet didn't sound like much fun. Nor did 1500 kills outside Gadgetzan. So I did what anyone else would do: stopped.
Okay I lied. I instead started running Dire Maul. Each key drop means 250 rep for all goblin cities. Each tannin can make a suit which is 75 rep each. Unfortunately I'm short on leather. Rune thread comes from a vendor and I get more than enough cloth for my tailor to make bolts. I can get around 6 leather per run from looting the supplies he leaves behind, which will add up to quite a bit.
By my current estimate, I need to free Knot about 60 more times along with making ogre suits as I get the tannin. That is a minimum of one per run, but I can get up to three if I'm lucky.
I have the terrible suspicion that this is the easy part. I don't know where to even start with the elf rep and darkmoon. My rogue will have to empty her bags to get ready for mass-pickpocketing. I might respec for the higher movement speed and shorter stealth cooldown just so I can efficiently steal-kill, steal-kill.