Here is a potential that (superficially) looks more like an atomic potential. In the band structure the lowest band is too narrow to be resolved (on this energy scale) by "bloch". The second band is about one and a half eV wide and the third about 14 eV wide.
The electron density on the left is that appropriate to the lowest "odd-symmetry" atomic state from which the second band is derived. Check the psi or "red fan" representation to verify the odd-symmetry of this state.
Bring the atoms closer together (a = 1.5 Angstrom) and set the energy range to (E min = -199.1, E max = -198.7) if you wish to broaden the lowest even-symmetry band enough for "bloch" to display it nicely. Interpret the phase of psi plots as you select energies at different points in this band.