I'm a fresh postdoctoral fellow who's just landed (2 months) in a new lab. The PI here has a great interest in exploring a line of research that I'm keen on pursuing for my future career.
Despite good funding and a well-endowed facility to count on, he has no major expertise in that area, nor a real model to work on at the moment.
I accepted his offer being somehow aware of the risky situation, but now that I've started, I understood that things are quite more vaguely defined than expected and I started feeling quite insecure about moving my steps in an unknown subject (both to myself and my supervisor).
He is very established in his domain and has a big multidisciplinary group, with many different active lines of research.
As a result, there's very limited supervision on projects, for the lack of available time.
On top of that, the absence of a model to work on implies building it from scratch, on very preliminary hypotheses. All this obviously means extreme uncertainty and a lot of time-consuming trial and error for setting things up.
Well...my gut feeling is telling me that it's too much of a risky pathway to undertake, with dead ends waiting around the corner.
And in these dire times, when a strong and extensive publication record is essential for academia, I am thinking about an early leave, searching a more established lab on the same subject, to have at least a more solid/defined ground to move on...should I stay or should I go?
Any comments will be greatly appreciated!

If it was me, I would stick it out whilst trying to find something else. As you know, it's hard enough to find one PD, let alone another one.