Allow "operators" (common in C++ such as == or !=) to be defined in classes
Class method names are restricted to alphanumeric as far as parsing / code generation is concerned. Being able to define == or != or < would be useful, as is common in C++. You can do it in the editor on the right, but then it cannot be parsed, and any arguments you put there will not be linked to actual types (so changing the name of the type will not update it in the method).
Methods, such as operator== (const TPoint &) const, are quite often used in C++.
I could not use StarUML without its support.