There are some things that can be configured globally for all admin elements. This is reference for admin bundle configuration with all default options.
# app/config/config.yml
fsi_admin:
display_language_switch: false
templates:
base: @FSiAdmin/base.html.twig
index_page: @FSiAdmin/Admin/index.html.twig
crud_list: @FSiAdmin/CRUD/list.html.twig
crud_create: @FSiAdmin/CRUD/create.html.twig
crud_edit: @FSiAdmin/CRUD/edit.html.twig
crud_delete: @FSiAdmin/CRUD/delete.html.twig
resource: @FSiAdmin/Resource/resource.html.twig
datagrid_theme: @FSiAdmin/CRUD/datagrid.html.twig
datasource_theme: @FSiAdmin/CRUD/datasource.html.twig
edit_form_theme: @FSiAdmin/Form/form_div_layout.html.twig
create_form_theme: @FSiAdmin/Form/form_div_layout.html.twig
delete_form_theme: @FSiAdmin/Form/form_div_layout.html.twig
resource_form_theme: @FSiAdmin/Form/form_div_layout.html.twig