Just a fun little question. In the old days villians would crossover over between the different hero's books, but over time it seemed the different editors kept a tighter and tighter leash on what they considered "their" heroes rogues gallery. So the question is what bad guy or group would be a welcome change of pace for a story or two for Spidey outside of the old tried and trues?
For me the top of my list would be the Serpent Society from Captain America. Those guys were not out to rule the world or get revenge they just wanted to get paid. That team to me seems custom made for Spider Man.