Well there were a lot of philosophies being thrown around at the time of Confucius. When he was alive the region was being fought over by countries and warlords, traditions were being ignored, and everyone was trying to find a solution. So if Confucius wasn't around some other philosophy of stabilization would be used.
Taoism was the biggest contender at the time, so we'd probably see that one become the leader in Chinese society. The smaller philosophies might also make some ground, but I don't see them becoming a major movement.
How this would change China, I'm not sure, I don't know enough about Taoism to really say.