I’m creating a new syntax .tmLanguage file but found that the colors in the default Monokai theme is pretty limited so I’ve created my own theme to give more variety to the colors.
Now when I select my syntax, I also have to switch theme to get the right colors. Is there a way to auto switch to the correct theme for that syntax file? Can you set a default theme for a syntax?

Preference -> Settings - More -> Syntax Specific - User
then just put the following in it:

{
    "color_scheme": "%PATH_TO_DESIRED_THEME%/%DESIRED_COLOR_SCHEME_NAME%.tmTheme"
}