I'd like to see battle grounds/missions/quests that would incorporate the cooperation of combat classes, crafters, and gatherers.
For example, missions where:
- you fight your way through enemies to reach a mining/gathering point and the gatherer picks up the valuable resources while the party members defend him from on going attack.
- you make your way through tunnels into enemy hideout and a certain rank miner has to dig the way through.
-you make your way through a overgrown part of the forest and you need a botanist to chop the branches down for party to proceed.
- your party needs to make their way to an overwhelmed outpost where Garlean army is attacking and Blacksmith has to fix the cannons while the rest of the party helps defend the fort.
- you defend a fort while blacksmiths and armorers craft weapons for NPCs that need to be armed, you can hold back the attacks but ultimately the crafters have to create enough weapons for NPCs to hold the enemies on their own

Just some ideas