I only send them on 18 hour venutres when I log out for the night, so I'm not too torn up about it. I do agree the "rewards" are meh...except when you get lucky. I've only gotten truly awesome stuff once..
I mostly use my retainers to gather crafting mats for me while I'm logged in and running dungeons/fates/ dailies anyway. I agree the high level gathering requirements are crazy - why would I equip my BTN with better gear than myself? silly.