This exchange perfectly encapsulates the problem with Siege - for established clans with active participation in Discord, the mechanics work well. As you mentioned Quinn, you make effective use of the prep stage to plan out who does what, and you use Discord/etc to communicate those objectives.
However, for clans that don't actively use Discord, the tools available are simply nonexistent, and the entire experience quickly becomes pointless.
You've given me an idea, though. What if, on offense, clan leaders/deputies could *assign* players to a specific objective? This wouldn't involve choosing what champs are used, or fighting the battles, or anything like that - it would simply give the player an alert when they login, saying something like "your clan leader has given you an objective in Siege", and, when they open the Siege screen, they'd get an indication on their screen as to what the target was. They wouldn't be forced to fight there, but you could add an incentive for them to - bonus florins or something to that effect. This could encourage people to target those lower stages, so that the people with better teams can wait until they are cleared out before using their teams.