[Suicide Junkie]

It at least has the outline of a Platonic Solid.
Such a design, however, is inefficient and unborg.

Spheres of Doom provide maximum volume (power) with minimum surface area (to protect).
Cubes provide plug and play upgrades to n^3 size & power.

Grim efficiency For The Win.

(You DO want the monstrous and scary classical Borg, not the wussy, lameified Voyager Borg, right?)