OOMEGA Incubator
OOMEGA Incubator is a graphical, form-based editor which greatly assists the metamodelling process.
OOMEGA Incubator provides the maximum amount of convenience for the software engineer and is perfectly integrated with Eclipse. Metamodelling starts with metamodel creation and definition of metamodel dependencies. In the second step you can actually design your metamodels as indicated in the screenshot.
OOMEGA Incubator is closed-source but reasonably priced. Thanks to the metamodelling language SDL - which is part of OOMEGA Core - you are not bound to buy it. Anyhow it’s a pretty good way to support us with a little "donation" which we will give back to you by means of new features.