Since one of the problems discussed here is that the new players don't get to fight the bosses because they're in the middle of a CS, I have a solution. To add: the vets do a disservice to the new player by steamrolling content. They don't learn the mechanics of the fight, they don't learn the boss' abilities and how to counter them. The vets just sabotaged themselves because instead of adding a new player into the pool of vets that know what they're doing, they are keeping them noobs longer by not teaching the or having them learn the fight. Onto the solution.

I think that in story missions only, level 50 story missions specifically, instead of a level sync, SE could apply an iLVL sync. If CM/Prae are recommended for iLVL 50, then all the people that are iLVL 100 will have their gear stats reduced to iLVL 50 standards. This way, they can't just steamroll through the content. They may actually need the noob who's watching the cutscene. The iLVL sync obviously won't apply to the optional level 50 dungeons, like Brayflox and others, just the story mode dungeons.