The ejector is just one factor involved. The brass hits the ejector, pivots around the extractor and is ejected. The direction the brass takes is a factor not only of the ejector and extractor, but also of whether the brass is hitting any part of the slide on the way out.
As for tuning the ejector itself, it is a good idea to take some stiff item, like a tin pieplate, think of it as the back of the cartridge case, then hold it where the extractor would. Then think of it hitting the ejector. You will soon see that the angle and position of the ejector will change the angle at which the cartridge case is thrown clear.
To bring ejection more upward, the case should strike the ejector lower. To move ejection down, the case needs to hit higher on the ejector. The adjustment is done by filing or grinding the ejector to obtain the right angle. It is very much a "cut and try" proposition, so take your time, don't get impatient, and you will probably be able to keep that brass out of your face.
Jim
