It would be nice to be able to send an object to back. I often to grayscale hatches and they can partially overlap a perimeter line. Typically I can just move everything over 100', move the hatch back 100', and then copy the linework back 100'. This way the lines are newer than the hatchwork, and thus are on top.
However, send to back would be easier, or am I missing something?
Look under the Edit menu commands. There are Arragement toosl. Also you could use a specific sheet (exmaple named hatch) to place all your hatching. Then move this sheet under the sheets that you want to be displayed on top
What do you know, it was there all along.