Spare lab coats - always have a clean lab coat on hand in case something important happens by. Readouts with the glass covers off - so you can change the readings as needed. A skylight - OK, more of a feature of the lab itself, but still essential. Ether Telescope and Microscope - to see things too small or distant for Ether goggles to pick up. Rubber gloves - for messy work.
Oil can - to get moving parts going right.
Espesso machine - for those long nights. Lab Mice - even mages need cute pets, never hurt them, only a cruel technocracy mage would do that. A Freezer - for cold storage of things. Acid of some type - to warn people away from. Many brightly colored chemical solutions Some Flourescent Fluid Silly Putty - for calibrating instuments, defying analysis, and use on the funny papers.