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because you dont have nin pick war use a sword untill lev 24 or so. Then change to dagger have a high lev heal you as you skill up on a EM.
When you do get nin you can sub it but ever job has good things to it.

Nin- Lev 20 you get dual 1 sword 1 dagger or 2 swords/dagger. lev 24 you can blink this helps if your SA does too much and the mob starts hitting you.
nin's stats are close to that of thf.

War- This works well for all out power and use of a sword better. more str and hp and vit help the thf but some loss of agi. War's skills come in handy
beserker and double attack can help later on.

Mnk-If you want to use hand to hand with your thf this is the job. With no loss
of dex and more vit and hp this job doesnt hurt thf. Boost, dooge, focus(sp?) can help too.

Rng- Pulling if you love it do this, and gil if you have it do this. The get the rang WS's more agi, but less hp, vit and dex a bit. But all of rngs skills will make you a good puller. Wide scane helps. Flee plus wide scane helps your pt in pulling exp.

Dont sub mages- I know you know this but if you dont please dont sub mage jobs gonk

Drk,pld,bst,brd,sam....-all the other jobs will not be as god as the top four dont use your time with them.

I must have spelled somthing wrong in there sad I hope this help you in picking a sub.