I think my biggest complaint on that original post, and probably why it didn't get any responses, is because the OP doesn't really seem to know what they want. They don't say anything about combining specific traits, only that they want to come up with something for meat, eggs OR just an ornamental. You kinda need to know what your goals are before you start out on some cross-breeding for specific traits.
Personally, with the price of feed being what it is these days, I can't fathom wanting to develop another dual-purpose breed. Unless you're keeping them primarily because you LIKE them, with eggs and meat just a side benefit, I can't imagine justifying a dual purpose breed, personally. The itty-bitty Mediterranean egg-laying machines that eat like, well, birds and lay like maniacs are looking better and better to me. And no ifs, ands or buts, NOTHING beats the efficiency of a good CX.