Because the Morph uses force detection, unlike most tablets and smartphones (they use capacitive sensing), you should be able to use most any “stylus” type implement provided the tip isn’t too narrow. As for specific suggestions of implements that work well, I’ll leave that to others who may respond.
And as for the Art Overlay, yeah, I don’t believe they’re producing that anymore. I suspect that either few people wanted it, or its performance was subpar.