Current Access Levels only offer "Create" or "Delete" for Templates. There should be an "Edit", meaning that all users of this Access Level shall be able to edit their own created Templates.
We are facing the situation that we were having 250+ Templates in the system, after years of no governance. So now we have put a PMO in place and we have taken away the possibility to create Templates from the Plan license (Access Level). It's only the Corp. PMO who can create Templates. However, we are now facing the situation that Template Owners every now and then need an update to their Templates and this all has to be done by the small PMO. We are still having 100 Templates in the system, after a massive clean-up (and still ongoing).