when i make pillows, 2 things are a must - piping and rounded corners. piping gives pillows that extra something. it takes them from being home made to looking store bought. i round my corners for 2 reasons. 1. it is easier for the piping to lay around a corner and 2. if your pillows are squared off, there is always a lot of extra fabric in the corners that never gets filled.
call me a pillow snob, but that's the way my mind works :)