Lets also cover the fact, that you can look at a few notable families and see that all or most of their characters hold high positions. It is not like having more positions is necessarily opening up those positions for more players.
There are certainly some players with most or all characters holding significant position. And just returns us to my other point, and the one Zakky emphasized, of not enough focus into all those characters and how they then affect their realms without that focus. And your counterpoint is hardly universal - it is leaving more positions to more players. Just as there are politically savvy/power hungry families with many positions, there are plenty of instances of realms with a character holding most council positions and plenty of realms that can hardly find folks to fill positions. If anyone wants a position,
it is not difficult to do so, so you will find families who suck up all they can as well as plenty of families who will take what is left lying around.
