I can't imagine keeping ducks indoors - or chickens. I plan on getting chickens someday (laying hens, just a couple) but mine will have a 10x10x8 outdoor hutch. We only have an acre so I can't let them free range. Anyway, I have done some research and, as stated before, they are social and need at least 1 friend. I have done volunteer work at a local "farm" rescue and chickens can be messy! (I'll agree that parrots are messy - I have 1 and he's all the indoor bird I need, that's for sure!). They like to scratch in the dirt and roll around and, well, be chickens. The ones I have met were nice enough but not like parrots at all as far as affection goes. They will kill smaller rodents (mice for example) and can react strangely to piercings and bright nail polish (at least the ones I worked with could, which were mostly Rhode Island Reds, silkies, some sort of cross, and various bantams - my fav ever was a RI Red rooster we called "Big Red" - he had "pet" mentality).
Anyway, good luck with whatever you decide! Make sure they are legal because there are few places that take them if they are seized.