First step should be to add a single checkbox to Wikipedia's internal search to search *all* namespaces, without having to check every single box. (Or is there already a way to do that?)
OH YES PLEASE.
There is no checkbox, but you can use the all prefix. Type into the search box:
all:douglas adams
and this will search all namespaces. If you wish to search one namespaces, use it as prefix:
wp:douglas adams
r.