I know it's probably getting translated to yaml from the old way which was a bunch of forms with build options, but we had some trouble with this. At the time, yaml releases were also still in development/preview mode.
One thing I'm going to miss is being able to discover things through the build wizard. Now it's just a blank yaml file and I feel that hurts the initial impression. I'd really like an option to build yaml files using the old way, but still get the yaml output for version control, that way I have all of the options and their potential values immediately available and I don't have to memorize and type everything.
There's a bunch I like about Azure DevOps though. Hopefully I haven't missed something really obvious.