Er. No I don't expect all my hauling to go through there.
I do however expect all the prepared food to be hauled through there as it currently is.
Otherwise the only hauling which should pass through there is: Depot hauling, and at various points, mass material hauling for the great red road I'm building (preferably entirely bauxite) the only pathway into the depot will be a LONG bauxite floor+paved road with the exception of right before the depot, where there is a bauxite drawbridge. And bauxite walls all along the sides too.
But back to the point:
the production levels have their own individual level of both input and output stockpiles. Output stockpile on top, workshop below it, input on bottom, in various forms of design.
Specifically:
Butchers, and breeding locations (probably going to begin with dog-breeding, see what elves bring me, if they don't bring anything cool in a couple years they might have an incident with my underground river water) go on bottom, with extensive stockpiles both above and below; some for rotting, others for bone, leather ect. Also on this level will be bonecarving and stone carving. Above the upper piles (output stuffs) will be cloth piles/leather, along with metals. That level will have another pile above it for output goods. Above such will be the prepared food/drink locations, above which comes grandhall, and mister system. Then 160 houses most of which are 1x3 +door (4 2x3 2 doored, and 4 22 tile + 2 door rooms per floor) between two floors, that then leads to the four towers I'm going to be carving out of the mountain (possibly rebuilding out of four different color stones, one for each of the four directions, which will each be quite tall probably housing dwarven sniper posts to deal with any flying creatures which might wander onto the map (10% megabeast dead for stoppage, begin check year 2; or giant eagles, or stuff from the bottomless pit.)
The real fun will be once I get my towercap farm set up, I'll need much more hauling so I can begin the glass-web between the spires.
Dwarven tribute to the GCS here I come (I really REALLY hope I have a GCS in my bottomless pit -- capture will be a must)