Thanks. From playing around with many of the suggestions in this thread, this seems like the best option. It is lightweight and easy to use. Exactly why I was using Insomnia in the first place.
+1 for restfox. moved from insomnia a few weeks ago. the UI could do with some polish but it's great other than that. plus it even has tabs, and can run in only a browser
[1] https://github.com/flawiddsouza/Restfox/issues/62