If I were arranging the pieces on the chess board in a way that makes the most sense (to me, anyhow), I think I'd want Charter and Altice (with one or more outside financial backers) to acquire Boost and whatever spectrum that T-Mobile must shed as part of their Sprint deal. Then Charter and Altice would acquire most or all of DISH's spectrum and gradually build it out (tapering away from reliance on the T-Mobile network via Boost as the new 5G network is built). They'd work with Comcast and Cox in a cable industry consortium to connect those providers' wifi hotspots into the Charter/Altice cellular network, plus use those cablco's coax/fiber networks as backhaul to both towers and small cells (4G/5G). Those cable companies would all sell their own branded cell services using the new cellular network (supplemented with their own shared network assets).
Comcast and Charter already cooperate on their current cellular services, Xfinity Mobile and Spectrum Mobile, although they rely on a deal with Verizon to buy access to their 3G/4G cellular network. Analysts do not believe this arrangement is profitable for either company.
Such a consortium would make the cablecos (whose landline coax/fiber networks are all in different geographic areas rather than directly competing with each other) first-class competitors in the wireless space, just as AT&T and Verizon, through their fiber networks, are first-class competitors in the home/business broadband space. The new T-Mobile plans to also compete in home broadband but through wireless 5G and 4G rather than a wired network.
I just don't really see what DISH brings to the table in terms of running a 5G network. They don't have any experience in cellular or in home broadband and they don't really hold any complementary assets, other than a shrinking cable TV service. I mean, if DISH is the one who ends up with the wireless assets, I wish them well and hope they make a real go of it as a successful 4th competitor. But I'm a bit skeptical.