Cup-holders.
Seriously, I’m not a mom or a dad but I have much experience with both. Mini-vans are just about ideal for carting around SEVERAL kids. My wife’s family came for a visit recently and we had 6 adults and three small kids to cart around. We almost all fit in a rented Chrysler town and country.
If you only have one or two rugrats, a decent four door sedan or small wagon will work. If Honda made a four door Element it would be great for small and messy kids (is that redundant?). Actually, I don’t know why no one makes a mini-van with a rubber interior like the Element. It would be highly kid resistant! (Nothing is Kid-Proof.)
My sisters-in-law value utility over luxury in vehicles. They should be easy to use but the extra goo-gaws like DVD players and sat-nav aren’t needed. Car seats should be easy to attach and remove. One sister-in-law even wishes she had vinyl seats for spill protection!