Hello Jantje. I now only use your plugin as primary tool for my projects, it is pretty stable and very usefull 
One thing i noticed, do not make a cancel during a burn of the arduino even if the burn is not working because the serial port remains locked (hard disconnect of the arduino seems to be enough to solve this).
And one request: would it be hard to offer the possibility to choose a different serial port for different project? for exemple to have a TX arduino project on serial 1 and RX arduino project on serial 2.
Do you know a plugin or third party tool I could use to remote debug on the arduino and do step by step?