Call duck questions

I am going to be getting call duck eggs at the end of May and have some more questions regarding the breed. I wanted to get all white eggs but the breeder said 6 is about all he could do for any of the colors he has, which is fine. So will be getting 6 white, and not sure what I want the other 6 to be. They have the following available: buff, snowy with chocolate snowy hens, khaki, butterscotch with blue butter hens, and blacks with black, blue, bibbed, and magpie hens. I am really not sure what other color I want to go with. If the ducklings grow up to be SQ I plan on showing them and need to know what colors besides white show well? I am leaning toward buffs. But am open to the other colors as well. Can you share w/ me your call ducks if you have any of the colors I have listed? I’m not to keen on blues. Thought about black, but I am also getting black Cayuga eggs as well and don’t want to much black. Any help would be appreciated it.

Also regarding call ducks can you sex them at hatch or not? If you can’t what age can you tell the difference between males and females? Does the male have that little curly q feather like other breeds? I have heard calls can be somewhat noisy/loud. Do the males tend to be louder or the females? At what age do the females usually begin to lay. I know there laying cycle is much different than chickens. What is there laying cycle? And do they go thru moults like chickens? If I end up w/ a few whites hatching and a few of the other colors to hatch as well I plan on having maybe a trio to breed. Do you have to breed like color to like color or can you breed different colors together? Obviously like to like is best, but in my case I don’t want to many ducks since I have lots of chickens already.

Any input to my questions would be greatly appreciated.

Thanks