Different Cursor and Sckew Option


There is already a cursor to select multiple objects, but can there be a cursor that only take the part you selected. Like if I want to cut a circle in half, I would scroll over only half the circle.

Also, can there be an option to sckew option to make it easier to tilt and object without tilting it. Like if I have a face on an object, but I want the face to stay straight.