It would so cool, if the declaration section is detached from the inspector. The inspector then even doesn’t need to be shown at all in the code view, which gives a lot more space.
Optically it would be cool if that declarion section would appear in the code-style.
I also think it would be cool, if you can display the code of multiple items, by multi-selecting them.
I made a quick mockup and screencast:
Here’s the click-dummy: