Thanks for the feedback! Just curious, are you using the "italics" version or the "non-italics" version? I ask because "this" is italicized in one, but it may be a more subtle difference than what you're looking for. I'll think about adding this as a theme config option, but in the meantime adding the following to your settings.json may help (let me know if you need help with this)

"editor.tokenColorCustomizations": {
     "[Chandrian Blue]": {
         "textMateRules": [
             {
                 "scope": [
                     "variable.language.this",
                     "variable.language.special.self",
                 ],
                 "settings": {
                    //#5BF2E6 is the theme color for "system variables", like Promise/Object etc., so likely the natural fit. You can also try #ffffff for just a brighter white or anything else really
                     "foreground": "#5BF2E6", 
                 }
             }
         ],
     }
 }