1. Great question, we've spent a lot of time cycling on this. There will be a "PI" for each group, but the sort of PIs we will bring on will be people who will give large amounts of autonomy to their teams--ie, each group will have a goal, and everyone in that group will be directed to work towards that goal in whatever way they see fit. But given the quality of the PIs we are planning to bring on, if they think a particular direction is really unfruitful, it is likely worth considering.

2. Not very unless asked.

3. Whatever the researchers want.