I wrote this post for another cubit, but thought that I would share it here.
When you are building your base of your own seedlings to work with - I have been taught to look for traits in the bloom that are unique. Try to develop the eye that doesn't blind you to seeing something that is wonderful just because it has 8 buds and 2 branches. If it has a trait you like, or more important, a trait that you have not seen elsewhere - keep it and USE it. Just because a plant itself doesn't HAVE all of the plant habit you want - does not mean that it will pass those traits on. It might take 2 or 3 or more generations to get the "entire" plant you want. I have seen over and over, in my own seedlings and in the gardens of some of the most wonderful hybridizers that the use of less than stellar plants can lead to some fabulous seedlings in the next generation. It depends on what you cross it to. These plants that don't measure up in all ways, but have a trait you see that you like are called "Bridge Plants." If you toss ALL of your inferior plants - you will never have anything of your own to work with.
Mort Morss is a good friend, and I was talking with him - oh, it must have been 10 years ago now. I was telling him about my lastest crop of seedlings, and that I was breeding for sculpting, but it was not showing up. How I was trying so hard to find parents to use. He told me to be sure that I was not SO focused on one form that I neglected to see the breaks that were showing up in other seedlings. He cautioned me to evaluate every bloom, for itself - and TO go off in a new direction if you find a great trait in your seedlings. I'll try to quote exactly (but is has been years) as I have always tried to follow what Mort said to me that day - "Follow the direction your seedlings take you. Don't have blinders on looking for one goal, and overlook an entirely new direction your seedlings are showing you"
The best advice I can give you is to try to go to hybridizers gardens, and walk their seedlings with them. Some hybridizers won't allow people in their seedlings.. others will. I learned so much from walking seedlings in Moldovan's, Hanson's, Brooker's, Norris, Rice's.... When you walk seedlings, the hybridizers will generally talk about traits of seedlings you are walking by. LISTEN to what they are saying. Really listen. Try to see what they are seeing by trying to look at the blooms from their eyes. Steve Moldovan was another one who believed in looking for the smallest trait in a bloom that he could work with. Of course, everyone wants a fantastic new blue daylily with 7 way branching and 60 buds... but you don't get there overnight.
Train your eye, and follow your heart - but don't go to your seedlings with a particular goal in mind, and only that goal, because you will surely miss a lot of wonderful bridge plants.
Jules