"Appropriate" depends on the kind of relationship you want to have.
For cap tables, remember than a board can issue as many shares as it wants to whomever it wants, diluting anyone at any time. So even if you could see the cap table, it offers no guarantees.
Maybe what you're looking for is whether their incentives are aligned around developing and keeping talent. For that you can look to the history of the principals: whether they are in for the long haul, if they stick together, and if they are happy to grow offshoots.
For cap tables, remember than a board can issue as many shares as it wants to whomever it wants, diluting anyone at any time. So even if you could see the cap table, it offers no guarantees.
Maybe what you're looking for is whether their incentives are aligned around developing and keeping talent. For that you can look to the history of the principals: whether they are in for the long haul, if they stick together, and if they are happy to grow offshoots.