Black Tack Pumpkins OR puff paint! I don't like the swirls (it isn't scary at all!) but maybe I could use white puff paint (even better if it were silver glittery too) to draw on a spider web and attach one of those little spider rings.
Fall / Halloween / Autumn - loving the pumpkins all in the fire place, very creative way to make it look appealing, love! But not the main fireplace! I don't love anything more than a fire going in the fall :)
Pumpkin in a lace stocking. I've planted a bunch of mini white pumpkins. White lace stockings on them might be a nice outdoorsy Autumn touch. Inexpensive and kinda unexpected. These might be cute on the outside tables under the arbor too.