I have reheated roasted veggies in a toaster oven. I try to prepare a lot on Sundays and Tuesdays and the veggies seem to heat up ok. Low temp while I fix the rest of my meal.
I have successfully stored roasted spinach & kale chips by letting them cool and then covering the container with press n seal, leaving one corner open. It seems to keep them fairly crisp for a few days, although the never last that long. The kids devour them!