You sound a bit like me. I get bored to death of having show quality stock that has only small room for improvement to meet a "standard". Progress in such projects can be painfully slow. I'm far more enthused by crossing two strains to create a hybrid, that often times is not only unique in looks, but grows faster and lays more eggs than either parent. Keep in mind that if you want good egg production, the cornish half may get in the way of this. Anyway, you can expect a lot of changes from one generation to the next on projects like yours - a lot of fun in my view. Good luck.