Yaru’s design is pretty good however the orange colours are basically intolerable for me and probably a lot of other people. There was an issue on the Yaru GitHub page but there are technical limitations that might make the experience a bit low quality. From what I understand, changing shell theme is handled manually in Ubuntu (Changing to the dark or light theme that is) which can cause the apps to use dark theme and the shell to be stuck in light theme or vice versa. Now adding colour variants would increase the extent of the issue. However using the user themes gnome extension seems to completely alleviate the issue. Basically what I’m saying is to use the user themes gnome extension and add accent colours.
Given Windows and MacOS already have accent colours and many other people probably also don’t like the orange highlights, this would be a great addition.