Group leaders need to have more control, not only at set up stage but during the whole time the group is together. A good leader will find a balance with their party on how the group goes forward, how objectives are met, and the level of chat within the party. However, any member of the group doesn't have to listen to the leader and can do what they want (zerging forward, activating mobs when the party is not ready, ending quests when the party is not ready, picking up quest objectives and not telling anyone what they've done). This results in the party leader losing control of the group and ruins the experience for the whole party.
Guild leaders already have the power to police their own guilds, so it is only right the party leaders should have the powers to police their own groups. People may abuse the system, but it doesn't take long for names to be passed around the server so everyone knows who are the good leaders, who are the bad leaders, who are the best guilds to run with, who to out right avoid.
I am warning people who want to run with me now to watch their backs in PUGs. I will join PUGs, but voice will be off, and I'll just sit and wait for instructions or follow the lead of the star. But as far as leading, it is really not worth it any more. Hence I am sitting in game watching the world go by. Yes, I can solo quests. But doesn't that defeat the object of a MMO?