ConjunctionJunction (Fellowship Manuevers were originally called Conjunctions) allowed for all of this. It also let the leader or their assigned delegate change the conjunction displayed in the plugin (note there was no way to set the built in conjunction display) from a list as well as assigning party members to a positiion in the conjunction with a pop-up reminder. It even allowed the leader to assign sets of conjunctions for quickly switching. Unfortunately there are multiple ways to start a conjunction some of which can not be detected by Lua so the pop-up didn't always work. Combined with the bugs in the Party API and the need for every party member to have the plugin loaded, this created a number of limitations. With the limitations, no one actually used the plugin so it was abandoned.
So, while it sounds like a good idea, given current Lua limitations it is not practical. Since Draigoch is the only content that really requires conjunction use, the current plugin that only works for the draigoch raid is sufficient.