In the batch file renaming feature accessed through the hamburger icon to the right of the File Name field in the Library module, I often need to search and replace particular text. I don't see a way to, for example, replace "Jan1969-" with "1969-01-", which I wanted to do this week because I had improved my file naming system and wanted to update my old files' names.
Even better would be to support entering an arbitrarily long list of replacements to make in one pass, with a "+" or "Add" button to add more "From" and "To", or "Old" and "New", boxes. For example,
Old: Jan1969 New: 1969-01
Old: Feb1969 New: 1969-02
Old: Mar1969 New: 1969-03
A further enhancement to that feature would be to give either the whole list or each entry a pulldown like in the Library module Text Filter, specifying Contains, Starts With, or Ends With.
I could actually benefit from a full-blown regular expression matcher, but I guess that's a bit much to ask of a consumer program like Lightroom.