Your Z home switch is Z = 0, so your Z max should be a little bit less than zero, which would be below the switch.
Using softlimits for the bottom of the Z travel is rather pointless. For it to do any good, you'd need to change it each time you changed the tool. If you're going to use softlimits, Z min needs to be less than the lowest point your Z will ever need to go to, with the shortest tool you'll be using. The problem is that when you use a longer tool, softlimits won't prevent it from going too deep.