The activity bar is the worst. Luckily you can move it and make it smaller.

  "workbench.activityBar.location": "top",

Just in case might as well try these..

  "editor.fontFamily": "'Monaspace Neon', monospace",
  "editor.fontLigatures": "'calt'",
  "workbench.iconTheme": "vs-minimal",
  "workbench.colorTheme": "GitHub Light",

  "window.commandCenter": false,
  "window.customTitleBarVisibility": "auto",
  "window.titleBarStyle": "custom",