The problem with this is that it defeats the purpose of having per-district representation in the first place, which is supposed to be about shared geographic interests. If your randomly cut districts end up including parts with vastly different interests, one of them ends up denying representation to the other. You can say that it averages out across the country, but again, the whole point of such districts is to have representation that is unique to their needs. If we're okay with averaging things out, we might as well just ditch the districts, and count party votes on the national level.