I get your point. But if a big university or similar would use the same slogan I’d still feel a bit odd. Sure, diaspora is meant to be able to let you communicate safely and with whom you want, but also for public and far away communication, work, interest groups and other cases. But maybe you’re right, it might just be my impression 
No, I understand, this is very personnal. I don’t have any opinion on this. I’ve never been very good at finding catchphrases.
Reading what others have said around the technical aspects of data privacy, it’s difficult to make a case for true privacy on Diaspora - on the other hand, the upside is that the people who are handling your data are not huge corporations. Moreover, the principles behind Diaspora for me, are the sales point. The https://joindiaspora.com/ website has a nice start.
For me, Open Source is a big deal.
Also, being in control of your own data is huge. It’s kinda like the “know your farmer” thing in the local food movement - instead it’s “know your podmin”…
People who are worried about food safety say that you should have good rapport with the person who grows your food. Likewise, I’d like to have good rapport with the person who’s managing my data.
I think it might be surprising to ya’ll, but given social trends around sustainability, I would tend towards something like “homegrown, open source, international”. Perhaps that word choice isn’t quite right, but this would be my choice.
Interestingly, I see that Pods could actually be tasked with creating their own outreach programs. Might as well take advantage of a strong suit here: the people who are hosting the data can connect to the users - in which case, the umbrella diaspora* catchphrase should be as broad as possible to allow for Pods to have their own flavors.
Anyhow, the Open Source element definitely has to be in there.
Also, I think there’s some elusive way to combine the community focused nature of diaspora*, with the local and international possibilities of decentralization.
continues mulling this over
PS.
Is the catchphrase not already: "The online social world where you are in control"https://diasporafoundation.org/