I agree. The 612 is a [relative] bargain that would make a great DD. And the fact you have kids makes even more of a compelling argument. The back seat will allow you to drive it more often.
When the 612 came out the dealer in Milano gave me a test ride. He pointed the car at a roundabout and floored the right pedal. The cars tires squealed as he calmly steered the car around the circle. I was impressed big time.
I vote big V-12 and the 612!!
Current: SA, 330 GTC, Dino, BB, QP
Past: GTC, BB, QM, C/4, 355, 360, 550, 575, C/4