We only drive in on the morning of sailing if we're cruising without our kids. When we do that, we opt for a later check-in time. I think psychologically it helps me not stress as much because we're not "rushing" to make a certain time frame. Plus I also hate lugging around carry-ons even if they roll.
No matter how late we board, I still won't eat lunch ashore because my first meal has to be Mongolian Wok. It just does. ๐