I completed my first writ last night(woodworking) and got a bunch of loot related to my writ. When I filled the writ I figured I'd make the cheapest stuff I could to see what the reward is. My questions is would I get better loot if I turned in higher level items?
No, the items' quality creating for the quest of the crafting writ don't matter.
You did enough by creating the simplest items. Their quality doesn't matter, so the style and their feat.