In case you want to have your default gateway on a higher metric interface (so slower) and only use the lower metric interface for specific routes

SetupStaticRouteThatOverrulesDefaultInterface.bat

REM If you want to set metrics on interfaces go to the confguration of the network interface:
REM (THIS IS NOT POSSIBLE WITH THE route COMMAND !!)
REM Goto: 'Internet Protocol Version 4 (TCP/IPv4)' -> Properties
REM Goto: 'General' -> Advanced
REM Goto: 'IP Settings'
REM Uncheck 'Automatic metric'
REM Type in the metric you want for that interface in 'Interface metric'

REM Find out what the interface number is
route print

REM The actual script (copy paste this into a .bat which you run with Administrator privileges)
REM It keeps correcting the routes, since Windows constantly updates the routes again to its defaults
:loop
REM Delete default gateway route on lower metric interface
route DELETE 0.0.0.0 IF <INTERFACE NUMBER>
REM Add static route on lower metric interface
route ADD <NETWORK ADDRESS> MASK <MASK ADDRESS> <INTERFACE GATEWAY ADDRESS> IF <INTERFACE NUMBER>
timeout /t 20
goto loop