Coding up every UI element by hand is a time sink, and suffers from a whole bunch of drawbacks. It’s not worth it. Storyboards suffer from all the problems you mentioned and probably more.
Back in the day, iOS 7 and earlier, we had a much better solution that is still useable today… xib files. No conflicts because every view controller and many of the views each get their own xib file, and you still get all the visualization benefits you mentioned. The only thing you loose with xib files is the navigation aspect, but as you said there are plenty of resources external to the app that hold those.