Breeding a dog with a wolf results in an animal that eventually forgets its training, or simply ignores instructions because it’s bored. Domestic cats are like that already, so what difference does breeding one with a serval or jungle cat make?
Both of the aforementioned species are near the low end of the felid size spectrum, btw.
I guess the difference is whether it is going to eat the baby.
But feral cats account for plenty of wildlife/small game deaths, introducing another, potentially more efficient hunter into the North American ecosystem is simply not a smart or sound idea. Among other reasons, if O`Bozo keeps up his efforts, we may well need that small game soon. Don`t like the idea of people having to compete with Kitteh and his bigger cousins for rabbit or squirrel stew.
I would think that it would take several generations removed from a wild to get that “wild” out of them.
But just the same, once it figures out that it can kick your butt, it will.