Glass Kiln

It smelts everything a plain Furnace handles, it unlocks the glass furniture line, and because the game treats it as a Campfire as well it quietly hands out the regeneration buff to anyone standing near it. That last part gets forgotten constantly, and it is the reason a kiln parked in the corner of an arena is not wasted space.

If you are laying out a crafting room, this replaces the furnace outright and frees a spot on the wall. It does not cover the hotter stations, so keep a Hellforge nearby for the ores that need one.