Joshua 10 recounts how the other Canaanites attacked the Gibeonites for making peace with Israel. I think this demonstrates that almost all the Canaanites had no interest in making peace with Israel. What is interesting is that not only does Israel come to the defense of Gibeon, but so does Yahweh, sending down great hailstones and killing more of the hostile Canaanites than the Israelites kill. If God was angry that Israel had made peace with Gibeon, this would have been the time for Him to show it. Instead, He Himself comes directly to Gibeon's defense. I think clearly, God's main desire was not to slaughter the Canaanites. If they had chosen peace, He would have been happy with that.