When you are looking at V5.30 there are several things in general that you will find as a common theme in the new release.
The first is to look at many enhancements in the area of enhanced 3270 user interface (e3270ui). e3270ui is getting more robust and is finally becoming industrial strength. Some of the things you will find in the new e3270ui include:
Improved diagnostics and deployment flexibility
Expanded history and near term history capability
Additional trace/analysis support
More robust cross tool navigation using what is called embedded data
History is going to be a big area of enhancement in V5.30. Look for quite a few new capabilities in the area of history.