while creating macros to delete full string was impossible to set shortcut Shift+Del for it (like in Visual Studio, you know). Ctrl+Del works fine but Shift+Del is easier to use.
also, why already used shortcuts couldn't be stolen from commands? say I need Alt+C, but it used with some unnecessary command for me. Why TeXstudio just cannot ask something like "current shortcut is already in use. Are you sure you want to redefine it?"