Definitely depends on the vibe of the event and how many people are there. we had like 40-50 and a cocktail party vibe so I opted for conversation peices and a scrapbook where they could vote for wedding themes. it was wildly well received and gave everyone something to discuss. Like the established ice breaker of the evening.
I think the honeymoon idea is fantastic- it's a conversation starter, gives the guests something to do so you have time to greet everyone, and it's not difficult on your part because there's not much to organize!
You could also do date night ideas, marriage advice, or anything else fun that your guests would enjoy!