The Priority Criteria for Selecting The Principal Advisor Long story short, I have left behind a toxic PI and now I am considering applying for another labs at different demographic locations, however, I found it little bit harder to make a thorough decision. One of the challenges that hinders me to make a selection is different feedback from many students from different labs, I have asked them and there is their response as follows.


A star professor at a high ranking university:  One of his student told me he doesn't have time to manage the lab by himself and as a sequence, he hired postdocs to be intermediate between him and his students. In retrospect, the student informed that he had tried to leave the lab at the beginning, however, they continue and mentioning that he benefit from his PI's reputation. Adding that, he and other colleagues suffered from anxiety and chronic stress due to the demand of having highly quality research papers.
Intermediate professor not very well: His student told me he is not qualified to work with students, but the student told me that she doesn't feel so much pressure on her research.
Junior PI: I think it could be risky as I don't have any background about their supervision history. However, what makes interested to contact them as they did good research and we have the same passion for this research line which triggers me to contact them.


My previous experience with ex-PI, he was not junior and not star, but he did research for more than 14 years, however, he didn't help me in my research or even writing papers besides being abusive and very destructive person.

The question is : If am going to select the new PI which very critical decision, how I should consider these scenarios, for sure, I avoid PI in  the influence circle of the ex-PI as I have been advised before, but what are other key corners I should bear in my mind.

I know we cannot make sweeping generalization, however, I would like to hear from the academia community if your have any prior experience or recommendation I should consider to make a reasonable decision regarding the PI selection.
There are multiple facets to this.


Quality of research
Reputation "rubbing off"
Quality of mentoring
Amount of work and stress
Personal ties
I've surely forgot something.


The major problem is that some parts of this might be more important for you than for me and vice versa. So, the basic thing is to decide what do you actually want from this position:


Get a PhD and leave
Qualify you for further academic life
"Parking lot" until you have found a better position in the industry
Have fun
Whatever.


This impacts a lot on the "weights" on the above qualities. Further, in my experience it's never a broad choice, but rather a sequence of binary choices. Say, the junior PI approached you first, you declined, the gossip in the staff room got to the star PI, he did not suggest you a position. It's an extreme example, but it's not "should I go with PI A, B or C", it's "should I take an offer from PI X or not".