Surely pattern picking is more accompaniment than melody playing. To inject the melody you have to introduce pinching, playing two strings at once, with thumb and finger, since the melody notes normally occur on the beat and in pattern picking the fingers are filling in in between the beats. However, I agree it is a great foundation or springboard for then going on to playing melody, as long as you can regularly break away from the repetitive pattern with the fingers, not thumb, to follow the contours of the tune. Patience is needed though because that can’t be mastered overnight.