Purrely has more varied interaction points. If you want to play around dark ruler and other mass negation, you can hold purrleap. In melffy, unless you are running playhouse, mass negation or book of moon effects hurt a lot more
Purrely spright is pretty standard. Max out the purrely quick plays, 2-3 small noir, 1 leap, 1 double cross, normal spright lineup, 3 angler, 2 beaver, etc. The only thing people argue about is whether to run the light purrely.