buy eggs from multiple donors that look the same but have different bloodlines
or, buy eggs from multiple donors that have looks you like, especially if you buy them from a different production resource environment.
bulls for semen are waste of time, semen storage on semen that never sells, endless discussions of a bull might hit, never does, need to keep it out of the market because someone will get something over on you and you end up with is a bunch of storage on bulls that will not even cover their collection fee, let alone the hot air discussing keeping semen locked up because 20 years from now, some one might buy it and get a hit and they never do.
probably there will be crickets of stories (irish whiskey, ali exceptions) of more than 20 stories of someone getting something over on someone because they sold semen, made a better bull and made more money off that bull rather than other sales.
there are very few semen sales bulls and the bull studs are full of semen that never sells, bargain sales etc.
if you don't focus on the bull, you don't have to focus on the bull, because you will have to replace him anyway.
bulls are mostly a waste of time and money for anything other than breeding.