Magnolia 5.4 reached end of life on November 15, 2018. This branch is no longer supported, see End-of-life policy.
Make big use of small apps. They are perfect for editing single things.
Small app is a design pattern that works well for editing:
Use the small app pattern for tools and configuration tasks. A small app is minimal and focused, reducing complexity even beyond content apps.
You can see the pattern in practice in:
Visually the small app is a basic gray container that contains a form. You can add many of these gray boxes into a single small app but keeping true with the purpose of this pattern, keep it simple. It is an easily recognizable layout.
About Magnolia app:
RSS aggregator configuration: