If you use:
Smoothing = true
On your display settings, to nicely scale your graphics for different resolutions, Smoothing = true does a really nice job.
But ensure that you don't have:
Graphic = SomeGraphic
Position = (100,100,0.0)
Smoothing = false
..left on. Having smoothing on the display, but no smoothing on individual objects looks terrible.
This might seem obvious. But my settings have been like this for weeks on Bean Farmer Pinball and I didn't notice it until today when I went hunting for the cause. I don't know why I had them set like that.
So now it looks great again. Just a tip to sometimes go looking for the most obvious cause first.