I like a good user interface for webmasters, so a clear menu path is necessary. For the admin toolbar dropdowns, I usually create subitems programmatically. Below the code to add a subitem to 'admin/content' ("Content"). You could stick these in a drush script after installation, to get these created automatically after a fresh install of drupal.
use Drupal\menu_link_content\Entity\MenuLinkContent; MenuLinkContent::create([ 'title' => 'Add content', 'link' => ['uri' => 'internal:/node/add'], 'menu_name' => 'admin', 'weight' => 10, 'parent' => 'system.admin_content', ])->save();