Reborn means u loose 99 lvls (not 100, and gosh whats with all that math >.<)...
If your STR<INT then u can be:
priest
wit
seer
But if your STR>INT then u can be:
warrior
killer
knight

Priests cape give mdef, and if im mistaken pls kick my butt. Their sets Give mdef matk and some spd (again, kick my butt if im wrong)

Wits cape give matk, their sets give mdef and matk (and yet again kick my butt if im wrong, and this applies to everything i say XD)

Seers cape give spd, their sets give spd and matk

Warriors cape gives def, their sets giving atk and def

Killers cape gives atk, their sets giving atk and spd

Knights cape give spd, their sets giving spd and def

The INT<STR are warrior types jobs, and INT>STR types are mages jobs
At rebirth u loose 99 lvls as many ppl said, every job has its own speciality, like 10% attribute or getting spd from yoru own pet.

If you go tanymore questions, pm me and ill respond asap @.@