Look down a few posts at Dragoon's Max Status

Quickest upgrades are probably:
Cobalt Haub/Tortiseshell Scale Mail/Darksteel Haub with PIE, somewhere around 30+.
Felt Bracers with STR, again 30+ optimal.
Upgrade jewelry to +1s, slap on a tourmaline or rubellite bracelet depending on what you need.

STR/PIE are always better until you hit the caps.

Quote Originally Posted by Bartleby View Post
The chart you posted is from a post that dates back to January. I believe that chart is out of date. If you look through the STR/PIE/ATK testing thread you'll find that stats have had major changes since then. As of right now the returns are about:

STR = 0.8 dmg per point until you reach ~350
PIE = 0.7 dmg per point until you reach ~310
ATK = .35 dmg per point

You can find the tests/data on the 2nd page of the thread.
My own testing on DPS vs Attack Power confirms ATK ~ .38-.42 dmg increase per point