I would look at what hybrid cross would be best for you, rather than spending all that time on a new strain. Getting all of the qualities to "breed true" in the following generations is the hardest part, and you would need to produce a LOT of chickens, grow them out, feed them, house them.. and then make a selection of them for breeding stock to continue with.
It isn't something you can do with 20 chicks, it's a much larger scale than that to make progress. Over the course of several generations.
Someone mentioned Silver Appleyard ducks. I went with Saxony ducks for the same reason. Big heavy bird, good tolerance, even temperament, great egg production for a duck. I hear not as greasy as a Pekin, but I won't find out for several more weeks when the extra boys are grown.
Bonus, boy ducks don't crow.
2 of my ducks, both girls, are the result of a wild type mallard male over a pekin female. They are MASSIVE, every bit as large as the Saxony, colored like a Mallard, I'm curious to see how they lay. Perhaps in the Spring letting them live with a Saxony male, and seeing what I get out of that as far as a utility duck. That way I could sell more Saxony and eat the crosses myself or something. I found a processor nearby so that I don't have to do the dirty work.