You might want to make some of that stuff as objects. At least in Maptools some items can be manipulated. A pitch fork could be used as a weapon, Horseshoes could be used as thrown projectiles. I'm still learning the VTT stuff myself so not sure what all matters, maybe some of the more seasoned VTT guys can tell us both. Still, since you are making all the items yourself I don't see it hurting to create them as individual .png files because then folks can place them wherever they want them AND can even use them in other maps they create, thus expanding the usefulness of your project. At least that's what I think. The items all look very good to me.