( 1055 Early Winter to onwards ) Here we have our magma smelters and forges, a glassmaker even though we have no sand, etc. We've still got plenty of future space for more things later.
The magma below here is cut off from the volcano by an obsidian plug. You can see the pumps and channels which brought the water up for that (and which are now draining slowly with the backflow-blocking floodgates opened) if you at the other nearby z-levels.
( 1052 Mid Summer to onwards ) This is the same as the waste management system that I came up with in the old version of DF - each refuse stockpile space is a one-tile space behind a door, except for the shell/bone/skull stockpile in the middle which also serves as a hall. So, anything which generates miasma will do so in a one-tile space behind a door, which a dwarf will never have any reason to enter (until it decays entirely and no longer generates miasma).
A bit more explanation:
I designated the center bone/shell/skull stockpile first, then designated the regular refuse stockpile so that it covered all the tiles behind the doors (it would cover the bone/shell/skull stockpile too, except newly designated stockpiles will not replace existing ones). The stockpile for the spaces behind the doors allows all refuse except for bones, shells, and skulls. The center (bone/shell/skull) stockpile is set to take from the regular refuse stockpile, so when something decays into a bone/shell/skull, it gets moved.