Sing a song and change the lyrics to be about the couple.
Put out pictures from the wedding.
Show a video from the wedding with funny moments, guests wishes, bloopers..
Have music at the end to add some simcha
I think bringing a little fun into a Sheva Brachos helps alot! The couple is in the most major adjustment period and emotions r running high, it should be a good way to lighten things up and add more Simchah (not torture, bore and exhaust them.)