Most of these are claiming to be some kind of new thing. But if you're coming out of an agency, trying to hire people who work in other agencies, the danger is you'll end up with just another variant of an agency. Sure, it might have better laptops, the structure may have mutated and the working culture might be tweaked, but most of these new agencies seem to be built on well-understood principles with well-understood types of people working for them. This might give you a temporary moment of interestingness, but it'll only take a minor manoeuvre for someone to catch up.
So what would you do to create a brand new agency?
Hire some digital natives. People like me who think that digital is "a thing" are old-school. We might be able to help get you through the next few years, but unless we become less in awe of computery things, we could end up making ourselves obsolete. Once you've got people, you'll need to create a guiding principle that celebrates the media environment we're dealing with. Embrace fragmentation and change. If you're trying to launch a killer agency now, where do you think clients need most help? Where can you command a position of unquestioned god-like genius? On my list, marketing and advertising wouldn't be at the top.