green goblin is fast, strong and able to take more than his share of hits but what would give him the edge is his fast and maneuverable goblin glider and all the crap he keeps in that sack of tricks of his. his pumpkin bomb barrages [explosive or gas] and whatever might be his 'tool' of the day. and if i remember correctly his gloves could shoot lasers that were pretty strong.
i think he could fly circles around atomic skull and just play with him till he is bored and unload his more potent weapons.