With my long beard (not reaally, it will not grow long), I have the imagined perspective of a seasoned adult.
And that is the point. How many of the issues we see posted here would simply solve themselves if we, you know, "act" like adults? Hmmmm!
The (fairly) recent revision of the Cub program was meant to facilitate this kind of den/pack structure/meeting scheme. With the dearth of adult volunteers, it allows one leader to oversee multiple dens and/or ranks and all meet at the same time. The achievements were also better coordinated among the ranks so that it's easier to have multiple ranks work on similar achievements.
Depends. In my neck of the woods, the entire pack meets every week. They will do a joint opening, then split into dens. Sometimes den meetings are done as a pack instead of individual dens.