manchild,
the nice thing about a conventional double-wishbone suspension is that the load paths are, for the most part, simple tension/compression. Your proposed trailing arm arangement, with its lateral offset, puts the trailing arm in torsion. With the aero loads produced by a modern f1 chassis, plus the fairly large offset shown in your sketch, I would anticipate a large torsional moment on the trailing arm. It also appears to be fairly long, so to achieve a stiff, responsive suspension, the trailing arm would likely be large and heavy. At least compared to a typical double wishbone arrangement.
Just my opinion. Nice pictures though!