I might doodle up a visual aid but most of the bituman peacefleet will be variations on the same design. A large sphere in the back for the engines connected to a very large, almost needle like cone. The whole thing trussed with three layers of spiraling corridor and compartments and armored by an ablative gel. Because of its conical design point defense placed further back can still fire forward without risk of striking the ship itself. There are no exterior apertures or openings of any kind as meson weaponry simply fires from inside the ship and point defense 'rings' float freely within the armor.