Is a ginseng ficus what you really want, or just what you’re choosing from? Lots of folks show up here with one of these eventually wanting to layer off the tubers in favor of the scion cultivar. They are a novelty and not typically long-term bonsai material. I’d suggest finding a F. nerifolia or a F. retusa because they lend themselves to traditional bonsai training techniques.
That said, of the three, the left one has the most solid base, so it would be my choice of the three shown.