Max stealing has multiple benefits. If you steal from players your chance of going unnoticed will improve and in town that can mean not getting guard whacked. Line of sight also helps in getting noticed or not.
Right, but I meant more like.. you can have stealing at 90 and use items to make up the difference to 120.
Temp I run for my pvp thief:
100 Ninjitsu (+20 from with ring and bracelet) (wolf form and shadow jump)
90 Snooping (+10 from Burglar's Bandana)
90 Stealing (+10 from bandana, +20 from shadow dancers)
60 Stealth (+10 from stealth epaulets, +10 from Burglar's Bandana, +20 from Shadow Dancer Leggings, +20 from Royal Guard Investigator)
60 Necro (wraith form)
So in the end it ends up:
That leaves 220 skill points open for swapping but since I champ thief a lot I usually keep tracking and detect hidden in there, but can also sub in a weapon skill or wrestling for added defense.
Suit is very basic minus artifacts. All just imbued pieces for max resists, 2/6 casting with mana increase and regen, and HP increase. Suit can be done without artifacts but you narrow your options with swapping skills that way. Also, I don't always run 120 stealth as 100 does me just fine. Harder to be passively revealed with 120 stealth though, I believe.