yEd is one of the most powerful free tools and it has few shortcomings to be in the big league. Understandably yWorks developed yEd as a showcase for the main library and thereofre a no-money product is not a good investment of engineering resources.
Is yWorks company is open to crowsourcing some of the development investment?
I would love to see the following features for example.
1. Object rotation
2. Layers
3. Import and/or export of 3rd party tools namely Visio drawings (until critical mass.)
I assume it it would not be hard to set up a system which people vote with committed donations to the features interested. yWorks would put a monetary sum to indicate the goal of the feature etc.
