Looks great but you will want more than 3mm polycarbonate for the lid and base- I'd say 6-8mm polycarbonate or 3/5mm aluminium. Also you need much thicker than 0.5mm steel walls- I've never seen anyone use tool steel as armour- a lot of people use hardox/ wear plates but then the thinner you get is 4mm. I've used 2mm steel or 3mm Ali which is fine for none spinner comps. A lot of people use 20mm hdpe as armour which will stop most things. Other than that it all looks fine