I agree with all of your points above. We have something really special with Hive, and the addition of a block feature will become more important as Hive grows. It will also be an important part of attracting others to Hive.

As for the technical feasibility of it? That's well outside of my wheelhouse, but I'm always impressed with what folks are able to develop here, so I'm sure that once the community demands it, someone will be able to make it happen.