Part of why we’re thinking electric fence is so we can eventually move them around the yard more, but if we do something more permanent, that sounds like a cool system.
There are many videos on the Justin Rhodes channel on YouTube where he uses a mobile electric fence from Premier One for his chickens. That is certainly an option as long as you are willing to regularly move the fencing before the chickens destroy your yard. The mobile fencing does not protect you from aerial predators, of course, and that was my main concern where I live. So I opted for a more permanent solution.
If you do decide to go with a more permanent chicken run, then I am a big advocate for turning it into a composting system. I have no problems with mud or smell. But I realize that some people might not want the looks of composting grass clippings, leaves, and wood chips in the run. One of the main reasons I got chickens was to make compost for my garden, so I look at all the composting material in the run and just think of all the black gold my girls are producing for me.