I am looking to build a template to replicate many times by replacing text and images from database records.

Currently, I am having an issue with getting the text elements appropriately aligned in the appropriate manner.  When I adjust the text shown in the attached image, the text should remain left-aligned to the second inner guide., but it should be vertically centered along the line which dissects the transparent rectangle, which I would like to use as a bounding box.

I have searched to discover the bounding box LPE, though it doesn't seem to work well with text that allows for multiple lines and wrapping.  Binding it to the path of Text element seems to fail (the bounding rectangle becomes invisible).  Binding it to a span also fails.

Assuming I can resolve this issue, my next iteration would be to indent all but the first line of any given "paragraph" within that text.  I've not gotten so far as to find viable solutions for that yet, though any advice regarding my alignment problem as well as the indentation problem would be further appreciated.

Maybe you have see the Next Generator extension: https://gitlab.com/Moini/nextgenerator

It will merge csv records into templates.

It's not clear to me if the template can automagically center vertically, but the extension author may have some ideas for that.

My issue would not be with the data replacement.  I will handle that myself through direct XML manipulation, because I need to bind complex objects, and I would likely be inserting additional elements accordingly.

My concern is mostly how I can get the text and the LPE bounding box to work, with multiple text paragraphs.  I'm assuming that each of these files may need to be opened again in order for the LPE to be applied.  I've also considered that I would not be bothered by the idea of realigning the text to a hidden rect which occupies that same reserved space.  I'm simply unable to work out the issues with the Bounding Box LPE when using multi-line wrapping text.

My goal here is mostly to minimize the required "final adjustments" that may need to be made once the files are generated.

Clearly Inkscape isn't the best document layout application. That said, here's a workflow that might help you. 

I see that my browser doesn't properly align the text and frames. It looks perfect in Inkscape.