Stay away from versus threads that compare languages to use.
An application can be designed in such a way that it answers all your priorities you have listed, regardless of the language you use.
1. Speed
Design your application so that it harnesses the language's preferred method in processing either the data or the interface.
2. Each System Can Work
It will not only work if the application is designed improperly and addresses the wrong issues.
3. Be easy and quick to learn
There's no silver bullet in developing well-designed applications. It takes years. Read Joel On Software's article on good software (http://www.joelonsoftware.com/articles/fog0000000017.html)
4. Sufficient for Visual Programming Library
I did not quite understand whether you mean here to have a tool (like Visual Studio) to assist in the development efforts or using the tool for visual development. As most interfaces today are used with a variety of front end tools (HTML, CSS, Flash, jQuery, YUI, GWT, etc.), this marks a separation on the codes needed to process what they take and present.
5. Sufficient Documentation
I reckon that for all languages you mentioned, it would take more than your whole lifetime to be able to digest the amount of documentation for each language. Know topic you need to look specifically to address your needs.
6. Business opportunity
A well-coded and well-developed application in itself sells for its services. Enough said.