Have you considered bifacial panels to get sunlight reflecting off the pavement? Depending on albedo it's perhaps (up to) 20% more power, but the panels weigh the same.
For direct DC-DC charging you'll need to convince the car that it's connected to a Supercharger (or CCS1 via the adapter), causing the vehicle to throw the internal switch and directly connect the charge port to the battery. This is followed by continuous communication so the car won't throw a fault and disconnect.