Although they are pretty useless for levelling due to the small amount of EXP they reward, level 1-50 battlecraft levequests do reward gear though, and, still have a chance of randomly dropping a piece of 'pink' aetherial gear during the quest from a treasure chest - it's the only way now to get aetherial gear as they've been removed from dungeons (which instead drop new green gear with unique colouring).

Unlocking retainer ventures and sending your retainers off on 'quick' ventures also have a chance of them bringing back green or even blue gear, depending on your level, their level, and the gear you've equipped them with.