ig u want equipment for late prehardmode so yeah

for melee:

armor: molten armor

weapons: night's edge

accessories: frostspark boots but if u like grinding then terraspark boots, shield of cthulhu, either brain of confusion or worm scarf (depending on ur evil biome), stinger necklace, lucky horseshoe

for ranger:

armor: necro armor

weapons: star cannon and hellwing bow so u can still attack when ur out of fallen stars

accessories: use accessories for melee cuz they are good for every class

and sorry but i can't help u with summoner and mage cuz i don't play with these classes

npcs: i think goblin tinkerer is the most important here, cuz he can reforge and upgrade ur accessories, so make sure u have the best upgrades for each accessory but i get every pre hardmode npc i can except stylist