Partly duplicate of FS#2515
Today there is already a $opts['showhidden'] but this not available for all search methods in search.php(to be precise, not for search_qsearch, search_index or search_namespaces).
Useful to add this?
Editable namespace template are possible by installing the plugin Templatepagename https://www.dokuwiki.org/plugin:templatepagename
, chose in its config names of editable wiki pages, and your template pages are editable by everyone you provide access via ACL.