I like the idea of item molds (not nessecarily "plate bp", but "Chest Emblem" that the smiths/tailors make into the item for you, either NPC or PC)
For weapons, its a bit more complicated. My theory is weapons should rain from the sky from trash mobs. You shouldn"t be able to clear a goddamned dungeon without equipping your entire raid in said weapons.
But they should be weak shit. If DPS weapon progression is 25, 50, 75 for raid dungeons tier 1-3, the tier 3 trash should drop 30DPS weapons (for example)
These weapons should then be augmented with different raid boss drops. These drops would be in the form of "spike of Striking" "Cuttleboner of Slicing" that would add varying DPS ammounts, and certain abilities. Say the Stone of Flaming Rage would add a +hate proc and lesser DPS, the Magmastone would add a utility clicky +medium dps. the striking would add major DPS, but no proc., etc..
These would be semi-class limited (melee vs priest vs caster); mainly by what weapon they can go into. That way, the bosses still drop good things, and can even have pretty rare "3rd" item types, that are plain items. Say each boss drops 1 armor "badge" 1 weapon aug, and 50% of the time one item from its loot table. This could be any slot, any item, and would have perks, but you"d be serviceable in your standard suit; Shields would work under weapons. In fact, it"d be fun to have different types of shields. the warrior would want a bit protective shield. The dark knight, he"d want his shield to cause damage to those who hurt him. The paladin might make his shield proc a heal on a bash; But, they wouldn"t be limited to only picking their kind of shield. The warrior could have a heal-shield.
To add customization, you could also make trash drop armor augs that would go in boss-made armor.
Off-slot items (rings, neck, mask, etc.) would be filled in through random drops, quests, unique boss-loot and what have you.
This might make 1-group trash farming a little more common, but it"d also make the trash clears semi-bareable, especially if you could turn in those random augs, or the base-weapons for fun to the quest hub of the dungeon, or your home town, for dungeon specific perks.
To use Naxx for example; you might get rewarded with some supply of holy water; which would aid you in further tackling the undead hordes. Holy water could be a big damage shield for your tank, a powerful AE that makes a certain boss encounter real easy; or a big trash pull easy; Could sanctify the ground, removing some boss"s ability to make shitty ass things appear on the ground.
A hundred different ways than "pure badge bullshit" and "fuck this random goddmaned druid robe again!"