It makes some sense that event 'A' can determine the direction of 'B', and so on, just because there will be a feeling of continuity and the events would be much more 'believable' because of this - it is a good idea!
The OP's suggestion that pivotal events occur only in open does, very effectively, exclude a proportion of the playerbase on console, poor internet connections etc. Solo, in such a scenario is at least presenting the best opportunity for everyone to participate![]()
I don't think (unless there is some Endor level CG coming) that any is 'pivotal' though. Having say, two out of fifteen open but in events that suit what open can do would be enough for me. But having a static shooting match for a CG is a waste because its not adding to events- having a Salome British Bulldog game across space would be fun and allow for people to defend / attack etc and be much more dramatic.