With the housing it should be like chickens, damp and pest free, well venalaited and space to spread their wings and sunlight. However pigeons should have perches the perches that you chickens use might be fine as long as the birds don't get to agressisve however box perches [ box shaped] or V- shaped perchs are suggested.
Also with chickens and pigeons they should be parisite free, with lice I give them a bath using human lice shampoo and some people worm their pigeons.
They should be feed a well-balenced diet, I feed the Breeders mix before I used to feed them pellets. Acording to some corn should be added to the mix during the winter, black oil sunflowers are rich in protein and my Birmingham Rollers love them.
They can be kept with small bantamn chickens although their may be some problems like the young squabs falling out of the nests and getting pecked.
IF you are going to put a shallow bathing dish in the pigeons pen during the summer change it daily, and make sure no squabs fall in and drown.
Baby Pigeons are called squabs and should be feed by their parents, it is sometimes rather diffucult tohand raise the squabs because of the special nutrition they get when feed by their parents, Of all the 8 squabs I hand raised only one lived to breeding age. If you do decide to hand feed them if the parents were to die you could use Exact a formula ment for baby birds
The information above is for pigeons in gerneral, depending upon the breed adjustments might have to be made.
Can I please see a picture of the "Feather-neck Fancies" . .