In the "Database records per namespace" section of project statistics all the pages counts include redirects. This may be useful for some research, but not useful for others, where only non-redirects pages are useful.
Whereas it's possible to find the non-redirect page count elsewhere on the page, I couldn't find the count of non-redirect pages in the Template space.
Version: unspecified
Severity: normal
I wasn't even aware that redirects also occur in other namespaces than 0, but of course why wouldn't they?
So yes this would be new metric, but not a trivial change (the scripts are rather hard to maintain) One or more intermediate files would need to be updated.
If you only need to do this in one languages it's probably easier to mine these data with a custom script, using the stub dump file with current revisions only. See e.g. https://dumps.wikimedia.org/hewiki/20140729/hewiki-20140729-stub-meta-current.xml.gz there is an atribute 'redirect' for every page title where this applies.
e.g. from some wiki:
<title>Main page</title>
<ns>0</ns> <id>1426</id> <redirect title="Main Page" /> <revision> etc