In the context of targeting atheists or any other group I would say this: I am not aware of anyone who can fill the "charismatic" shoes that SK referenced earlier, but part of what we are missing is a coherent message packaged in an attractive form (the honey on the rim) that can serve as the centerpiece of discussion for any group that comes together in an initial meeting.
Whenever a group of strangers comes together on ambiguous terms, something has to be done to immediately "take charge" of the conversation so that it isn't taken over by those with another agenda. That means being clear in our agenda, and presenting it in an attractive and non-threatening but firm way so that it is clear what those who might consider returning would expect in the future.
So for example while a group of atheists might come together on the basis of knowing that rejection of supernatural religion is part of the program, the rest of the program needs to be immediately up front in outline form so that those who happen to be atheists but who are otherwise categorically and constitutionally adverse to Epicurus (such as crotchety old men, nihilists, and the list could go on and on) could immediately be discouraged from trying to take over the meeting or discourage those who are sincerely open-minded.
I remember as I have mentioned before that Elayne was the last who tried a meetup group format, and she tried to use "Tending the Epicurean Garden" as a text. I think she concluded that was a huge mistake and just played into taking an already eclectic group and making it even less unified.
It's probably much more appropriate to use something like the DeWitt book, especially the outline form presented in Chapter One, to quickly convey to everyone the general outlines of the direction. But at the same time combine it with more immediate references to pleasure (potentially food, drink, outside activities) to establish that the group isn't focused on being a bunch of disembodied minds.