I've always liked Corel Draw for it's intuitive interface.

Click on an object and a frame containing 8 handles surrounds it. Drag a handle to stretch the object. Drag a corner handle to re-size proportional.

Click the object again and the frame corner handles turn into curved arrows. Drag a frame corner to rotate the object. Drag a frame edge to skew the object.

A bulls eye center of rotation symbol appears in the center of the object by default. Drag the symbol anywhere inside or outside the object to change the center of rotation.

All can be specified via keyboard input if you need precision.

Simple and clean.

Ed