20-1 Water/Bleach solution and heavier 10-1 Water/Vinegar solution is what we used a few years back when all three of our cats were sick at once. We threw away all their non-ceramic dishes, litter boxes and toys we couldn't run through the washer. After pulling the stuffed toys still damp out of the washer, we put them in the Microwave until they began to steam.
Not sure it really did anything outside of giving us peace of mind. Each cat got better after 5-7 days, with one having an overnight vet stay. Just a real mess with none of them being able to hold their food down. Fortunately two of them were still taking on water through the ordeal, and we were already seeing the beginning of recovery from the first to get the virus when the other two were stricken.
It sounds like you have the really important things taken care of, food dishes, toys and the litter boxes. Those should be the primary points of concern. The rest is just adding to your own comfort level and as mentioned before, definitely therapeutic.