Impressions

The first image shows the legacy mode of our standard application style (check last image). It turns a SDI application to MDI - without coding or re-deployment. Simply awesome

The second image doesn't use a toolbar and the third one is without a menubar. Not all applications need multiple navigation elements, known from desktop applications.

The fourth image shows, what we prefer.

Legacy mode (MDI)		Legacy mode (no toolbar)
Legacy mode (no menubar)		Modern mode (SDI with popups)

One more

Modern style (menu right)

[Update]

The same application with Swing UI

Swing UI