Most apartment buildings are monocultures, usually addressing the same part of the market. There often isn's much of a community outside of the lobby or the elevator.
C.F. Møller Architects and Brut Architecture are trying to change that with their new residential tower in Antwerp. They are piling different types of housing on top of each other in a sort of vertical community. The goal is to become "a sustainable and collective community." According to the press release,
...social interaction is enabled and encouraged in numerous ways without compromising the need for privacy. The proposal contains a large selection of apartments reaching out to a diverse group of inhabitants, from small types suitable for student co-housing to larger family and live-work types, all grouped into vertical mini-communities.
A full 25% of the area of the complex is devoted to balconies, roof terraces and "winter gardens"- enclosed year-round glazed spaces at the ends of the building. There is also a landscaped roof terrace and "a triple-height green oasis at the top with spectacular views over Antwerp and the river Schelde." There is a common dining room and of course, a bike repair shop.
The building is designed to achieve the Passivhaus standard and has no central heating system. "Great care is taken to mitigate the possible negative effects that tall buildings can have on the local microclimate, and to ensure a positive contribution at street level."
Their motto for this building is "bigger and cheaper". Good luck on that with this level of amenity and passivhaus insulation. But it is a model for how higher buildings should be done: break it up into smaller communities where people can get to know each other.
More at CF Moller.