Esme Povirk (@madewokherd) commented about dlls/gdiplus/font.c:
stat = GdipCreateFontFamilyFromName(L"Liberation Mono", NULL, nativeFamily); if (stat == FontFamilyNotFound)
ERR("Missing 'Courier New' font\n");
stat = GdipGetGenericFontFamilySansSerif(nativeFamily);
Wouldn't it be better to fall back to a monospace font Wine ships with?