Not a bad idea on the accent strip! Future pillowcases, I think, will have narrower bands - I don't really like how wide it is, but since it was my first time using that pattern I stuck with what they recommended. I think I'd prefer it about half that wide.
I have a pretty big stash of vintage lace - I think for my mother-in-law and my grandmother-in-law I will use a couple rows of lace as the accent strip. I think it'll look nice and it suits their style. I was also thinking that I could use some satin, for a little bit of shine... For my niece (who is super into skeletons right now) I have some ribbon with dancing skeletons that I was thinking I could use to gussy up a plain fabric strip...
SO many fun possibilities!!