If you turn in the quest, you still get to fight Atronachs. They are just neutral to you. It actually makes the farming easier. You don't accidentally aggro another group.If you still need this when you get to Dominion's Reaper's Marsh, there is a quest in a village called Willowgrove that requires you to kill Storm, Frost and Flame Atronachs. If you don't turn in, you can have a field day farming them.
Hopefully you won't have to wait that long and you will have your title by then though.