The items I generally do are at full fuse, although I did a plate with leaves that circle the rim and are tack fused. A customer wanted it and while I was a bit hesitant at first, I liked the effect and have done it a few times to good results. I also use frits and enamels and the like or put designs in the field of the plate– mostly geometric. I’ve done some frit painting on the field– I think “Peggy Karr” does the same thing– and I’ve liked the effect. I haven’t sold any of those yet– I’m in the process of refining the technique so that I get more consistent results– but I imagine they would do well.
I agree that color and finish are probably the two most deciding factors in whether someone buys or doesn’t. I saw a $600 plate at a gift shop that had what I would consider a rather lurid color scheme. I didn’t care who signed the thing, I really didn’t much like it. I have made plates from slumped stained glass and have had people oooh and aaah over them as if they were some sort of designer original.
I think the key is to make something that you would like to own or to make something that you could give to your fussy Aunt Mabel– who inspects it as if it were a diamond.