Would this be a lame 16th birthday party?

No but it could be if not done correctly. If that is your choice then make sure the whole theme is everywhere. Cups, napkins, plates and the cake. When they wear dresses tell them the theme and dress like it is a tea party for little girls. Then pink balloons and dolls laying around and little tes cups and other girly kids stuff. It sounds like it is the makings of a good party. If you need a KEN doll let me know? lol