Good call! (although we love the ducks too and they're laying like clockwork at the moment - husband wants more and more of them). We started with chickens last year with the idea of breeding them as well as for eggs - I went for Orpingtons because I love the look of them, there are lots of lovely colours/patterns and they're a local rare breed (I'm in Kent). I've had a bad run of luck with problems already with worms, mites, lice, coccidiosis and avian leukosis (the latter was the over-riding feature making them more susceptible to the rest). So I've managed to kill seven chickens so far - so much for supporting rare breeds - but still have six which appear well. At the moment two of the hens are broody so yes, Orpingtons do have that tendency.
Once I'm allowed to get new stock in again, I want to get a couple of hens for green/blue eggs (Araucana or Cream Legbar), a couple of Marans (dark brown eggs) and a couple of Sussex (big white eggs). I'd also like to breed some Dorkings because they're another local(ish) rare breed but I do have to make sure I can keep them alive first!
In your position I'd be tempted to get three different breeds of hens for three different egg colours but that's probably just me being daft - you're just as well off with some ex-batts who lay throughout the year.
H