Rabbits tend to do well with chickens, although females will almost certainly burrow everywhere, especially when in heat. Problems would arise from keeping multiple males though.
Ducks, but from my experience, not drakes. I had to separate the drakes from my chickens, due to overly amorous attentions.
As CPL said though, wait and see what mess the chickens make first before adding to the woes
Giving power to politicians is like giving whiskey and car keys to a teenage boy - P. J. O'Rourke (thanks Jessie)
It's amazing that people can believe everything is predestined but they still look both ways when crossing the road - Stephen Hawking
1 Wife, 3 children, 1 Staffie Bitch (RIP Marley), 1 Chi-Chi, 1 Tuxedo Cat, 1 part Maine Coon cat, male bearded dragon, Horsefield Tortoise, 2 White Silkies, 1 Frizzle Pekin, 1 CLB, 1 Appenzeller Spitzhauben Cockerel, 1 blue laced Wyandotte, 3 Appenzeller x Wynadotte pullets, 1 Call drake, 3 khaki Campbell ducks, 4 (2 male 2 female?) Aylesbury x Campbells, a breeding colony of Dubia cockroaches.
And a lot of Ibuprofen.