Two points in the hireling gives the best chance that a mail will contain the best mats (tempers, trait stones, racial stones, etc). Adding the third point gives you two mails a day (twelve hours apart) but slightly devalues the stuff you get.

So if you can get the two mails a day, go for three points in hireling, otherwise stick with two points.

Now extraction is supposed to improve what mats you get (tempers, trait stones, racial stones, etc), but also improves your chance of getting them when you refine the base mats as well. So win-win there.

Obviously you can't refine the runes from enchanting, but the extraction there should give you better chances of getting Kuta and the like. (please someone give us the odds, someone who understands it, not me).

You only need the points in Extraction for the Enchanting Hireling to get the Kuta's and Rekutas with regularity.

I have two crafters with L3 Hirelings (one has Wood and Cloth, the other Blacksmithing) and I have 4 mules with L2 Hirelings. I find the L3 Hirelings do give me more upgrade tempers from time to time (2 Gold Upgrades instead of 1) and I can get up to 6 different items from the L3, but only 4 from the L2's. But most of the time the differences between an L2 and L3 Hireling are not that great.

There is also the need to log in twice a day, about 12 hours apart, to get both emails, so the L3 is questionable. I have lots of extra skill points so I spend them on the L3 because what else am I going to spend them on?

Yeah... they need to put some verbage explaining this on the hireling upgrades. If I would have known this, I wouldn't have upgraded any of them to L3. I only have 1 time of day that I can log in which means my mats are less valuable for the same number of mails I will receive (one) than I would if I had at L2 hirelings. Wow. Talk about your wasted skill points!