it would be extremely useful if it is be possible to rotate the objects. It’s really frustrating when you need have some feature just for verticals - e.g. square brealine for rectangle - I would like to use it for mockup of the horizontal toolbar (very long, title on the left side, then nothing and then buttons on the right), but it is not possible
Also e.g. the line tool - very basic thing which is missing - only vertical and horizontal separator available make the designs limeted (since the arrow, only object which has more freedom, is much thicker than the rest of the elements).
In general you could have much universal and intuitive prototyping tool if you have less elements but with more freedom and options - e.g. one line tool instead of horizontal and vertical separators…