try this:

for Knight you want item with 50% block and dmg reduction (25% is max), other stats that are less important would be hp, dodge, all attributes, def
also most of your points go for Knight, I can just show you mine at 100t gold investment:

each Healer: 60k points in dmg / 300 points in crit dmg (still don't get this part, but it's nothing, so no harm) and on an item you want ofc highest tier dmg / all att
Warrior: you only need some hit (I have 10k points there) and an item with high tier hit
Hunter: you want dmg (20k), hit (22k), crit dmg (20k) and an item with those stats
Mage: more or less like for Hunter, but crit dmg is even more important (26/22/26 in my case)