Best language for System-Trading-GUIs?

Hello folks!

I am searching the net for some useful information, without luck so far, hoping to get some input here
I plan to develop a trading software, meaning a GUI to:
- analyze quotes and charts
- do paper trading
- test strategies
- program my own indicators
- display any wanted information in charts and tables
- ... and much more

very similar to programs like "prorealtime"(prorealtime.com/en/) or "Metatrader" (metaquotes.net/).

And now I am already stumbling before I even really started
Thought of trying to do it with Matlab, as I have some experiences with it and it offers some tools and easy GUI-programming, but now while building my concepts I have doubts, whether it is so useful at all or whether a language like C# or Java would be much better in the long run.

I don't need to analyze realtime-data (not yet), endofday is good enough, what makes the requirements much easier. so I need a language that can easily import quotes of a database, does quite some calculating with it and most important is able to display the data and charts in a GUI by which it is controlled.
I have no problem in working myself through a new language, I just need the vision, that it is the right one for my task.

I would be very grateful for some input and direction

Easier said than done . Java would be a better choice than C# for data handing, since it can better database support. On the other hand, C# would be a much better choice than Java for the GUI. If you want to be able to run the application on multiple platforms then Java is a better choice than C# there also.

You may also want to consider a more agile language; Python or Ruby maybe. Both are cross platform and have pretty good database support. They're certainly better than Java for the GUI.

Mark.