I wouldn't worry much about the committee, but I'd definitely suggest picking up a senior faculty mentor or three. I did my PhD with a fresh prof, and it was really helpful for gaining independence and learning how to set up a lab and collaborations and that has been great for my career.
But he wasn't much on mentoring, and I was completely on my own for the job market- he wrote what I hear are great letters, but that was it.
I had senior mentors in my department, as well as people I met through conferences that were a lot more helpful in those areas, but who's lab I wouldn't have wanted to work in.
As an aside, committees are pretty unimportant in a lot of the bench sciences. I met mine three times- once to ask, once for my prospectus, and once for my defense. None of them had any role other than evaluating my work. I know committees in other fields can be more involved.
