How do I configure my Juniper VPN client to work like the Windows VPN client to not be the default gateway for all traffic?
There may be another way to do this, but adjusting the Interface Metric under Advanced as seen in the following screenshots:
Adjust the Interface Metric to, eg, 10
After doing this, adjust your WiFI and/or Ethernet Interface Metrics likewise (I have Ethernet set to 1, WiFi to 5, and the VPN to 10). This [should] ensure that only "appropriate" traffic goes over the VPN.