[Redbaron]

I think split resistance is almost as important as disease resistance. I don't know if the trait is linked in any way to any of the traits you listed. I also don't worry too much about it myself. A knife easily trims the "scab" of a split area off before eating. But I have noticed that outside of people really into tomatoes, that is the primary "off putting" thing about heirlooms or otherwise great tomatoes.

Also there is a gene in fruit I read about. It is a specific gene for green shoulders. Increases the sugar and nutrient balance in the fruit many times over. (sorry I forget the name of the gene)

That I think would be useful in making sure the fruit are as frost resistant as the plants. It also is helpful in maintaining flavor late in the fall.