So ...

No on crowd control. Crowd control doesn't add any difficulty to the player, it just makes it easier for bad players to troll their group. Hard pass.

No to branching dungeons. Look, I absolutely love open-ended RPGs where you have these dungeons with sprawling paths. It's so much fun and excitement, but it's a horrible match for the current psyche of MMO players. You may get some good times in these dungeons for a couple weeks, but once an optimal path has been determined, players will berate and ridicule any tank that does not take the optimal path. It's an added level of toxicity that we can do without.