I remember when I was playing..I literally took a month and a half from progressing through the story to build up. I had a black mage maxed out with time mage abilities maxed out, a priest maxed with oracle abilities maxed out. If I had both of them nikkas out..nikkas were getting hit with spells with black mage while I had my priest casting shyt on the team to bolster defenses or go kamikaze on offense when needed.
Best to do it at Chapter 1, to grind and get new job classes. I had Ramza reach level 8 Knight, Level 6 archer, Level 8 Monk, Level 8 Thief, and gained the Ninja job class. Had him gain the "Counter" reaction ability from Monk, had "Move + 2" from Thief on top of steal Weapon, Steal Armor, Steal Accessory, and Steal Helmet, along with my other (Male) unit from my party the same thing.
Having Counter, Move+2, Concentrate, Poach, as a Knight with Ramza was
for Chapter 1. By Chapter 2, Ramza's Squire Class has the ability to have heavy Armor, shield, and Helmets like a Knight.
Anothwe MASSIVE tip is right before the last major Battle in Chapter 1, is that random battles in Mandalia Plains have humans in it sometimEs. If you check their equipment, they have some BEAST Equipment that not available to buy until (much) later in the game. This is when you need someone other than Ramza with Steal ability that already learned Steal Weapon, Steal Armor, Steal Shield, Steal Helmet. Ramza, as a Knight, should learn the ability to "Break Power" to break down any enemy's strength so that their attacks dont do devastating blows on your party members. Also have 1 or 2 Chemists to heal party members in need.
Basically, it will take a lot of time before you able to steal their Weapons or anything of their equipment successfully, so be prepared for the long haul. Once you do take it, finish the battle, save game, buy a ton of new potions/phoenix downs, and give the advanced swords/shields to Ramza. Once someone In The party is equipped with it, if you go to another random battle (not the very next one), the enemy Knight has even BETTER equipment than what Ramza has. Rinse and repeat until you get weapons like Crystal Shield and Rune Blade.