Bought a 16x16 concrete paver and printed some Ikea Lack brackets. Table is probably as sturdy as it gets now. Not sure if I need the rubber on top of the concrete or if I should just let the printer rest directly on it.
I was at Ikea, ended up picking a small pack of neodymium magnets from KMS Tools for the poop chute. Super glued the magnet and it's working very well. Let me know if you'd like one, I can drop it off next time I'm in your area.