Specific answers to most of the questions in this thread can be found in Olle Kjellin's Facebook group and more specifically in his PDF docs available there: (Olle Kjellin, not Olly.)
Pronunciation Best Practices (Facebook) https://www.facebook.com/search/top/?q=pronunciation%20best%20practices
Kjellin Practice Pronunciation with Audacity https://www.facebook.com/groups/best.pronunciation/?post_id=2488854401367750
He focuses on prosody and his main doc explains the theory, practice, and use of Audacity in about equal parts.
It's excellent and after reading it your biggest complaint will likely be hoping for more.
He describes how to use Audacity specifically but other programs can off course be used including Praat (although this is optimized for slightly different and more sophisticated tasks.)
Also, David Tolman of https://fluentlistener.com
(and YouTube) offers related material but more closely focused on being able to hear and decode the sounds of the language. (David's main focus is French, which I'm studying, but his techniques carry over to any other spoken language.)
For myself, I also do a lot of Glossika -- the old audio program, not the borked up website version.
Hope this helps some of you and we'll keep this thread going.