I thought the global drop rate petered out after the discussion on how best to do it? I know there was a patch somewhere that someone implemented one, but I don't remember an increase making it to the trunk.
Edit:
If you intended to go the "Treasure Hunter" route, you would have to create a new trait for each job. Traits are stored in the 'traits' table. I haven't experimented quite enough with it, but if you can't figure it out, here's some hints. I'm a big fan of giving people the pieces they need and letting them go from there.
traitid - Not certain, but I suspect this impacts what trait is shown to the player, or is used to keep traits from stacking/overlapping. I haven't tested it. I know I saw somewhere that this is limited to values less than 100, but that can be changed in the core if you go digging.
name - I suspect the server ignores this entirely, and that it's only for readability.
job - What job the trait applies to. Only one job can be entered here. Notice the duplicates, notice the differences, you'll learn a lot. To decode the numbering, open up your job's list. WAR = 1, MNK = 2, and so on.
level - Uh, guess.
effect - Hidden status effect, if there is one. Only ones really in use are regen/refresh. See /scripts/globals/status.lua for a list. Remember to convert from hex to decimal.
modifier - Similar to effect, but different in what it can change.
value - Potency, if it's applicable.
Keep in mind that just because something appears in the client or tables doesn't mean that it works, by the way.
For example, I believe the "killer" effects don't do anything right now, but haven't tested that. I know the circles will intimidate, at least. You'll also have to restart your server for any SQL changes to take effect.