I just tried out the lattice deform to curve the top half of the body, I would say it is okay as a deformer but the UI is problematic. When selecting lattice points you can also select object vertexes, it really should only allow you to pick lattice points, that's just bad design. Maybe there's a special procedure to safe guard against this but it's not obvious. This thing isn't going to have any personality until I get some wheels and windows on it, at the moment it's not really speaking to me, I should've started with the front cabin. I might start working on that next.