I'll recap. You made the point that a "better attorney" would go to the family and ask the family to decide what was best for his client. I pointed out that such a course would be a serious ethical breach by the attorney. In response, you posted in the example of an attorney who you suggest turns away potential clients for..., well, I'm not sure what your point is really. And I then pointed out that an attorney's ethical obligations to actual clients (which was the case in your original example) differ exponentially from that to potential clients (your John White example).
And since you just introduced the suggestion, the concept of "judge shopping" (really, forum and/or venue shopping) is almost exclusively a civil litigation concept; far fewer options are available to criminal defendants, at least not in the short term while your client is in jail. I'm not saying there aren't ways to manipulate the system to force different outcomes but they still involve unknowns and generally take months. While your client is in jail awaiting trial.
In the hypothetical case of Marsteller, where a prison sentence was hardly certain, an attorney going to the family of Marsteller, a non-minor even, to advise the family to leave him in jail because it'd show contrition (or even if you think it'd ultimately be for Marsteller's own good, to reflect on his conduct), would not only be committing an ethical breach, but would be an idiot because a sizable chance existed (and exists) that Marsteller would not ultimately have to serve time at all.