We only have four people in our family, but we just opted to take our minivan (rather than civic) on our recent road trip, as we could fit all our bikes in the rear of the van with the third row folded down. It was awesome to have our bikes with us, we used them daily. I think we will start doing it every year.
Whenever our van dies, we can't really justify replacing it with another van as we are only a family of four. So we will likely do a hitch rack. On the other hand, if we get another rocking deal on a van (free, lol, from a family friend) being able to shove the bikes in the rear might make the hit in fuel economy well worth it.