I attached the Anderson's to the battery with about 12" of #6 wire, terminated with #6 crimp rings for the 5/16 stud/bolt on the battery.
You can solder the connections if you don't have a crimping tool.
I was not worried particularly about falling out of the boat while underway, speeds were not really high enough to cause an issue, and if running shallow, just trim the motor up to just sub-surface.
But if I was capsized by a wake, which was far more likely, I did not want the battery to hinder my recovery. The weight of the battery would have easily popped the Anderson's apart.
Alligator clips might have broken away, or maybe not, if they were enclosed in a battery case. And they are not really a very reliable or efficient connection.