My husband travels a lot and typically has to drive with a load of tools and materials for his jobs. Instead of wearing down one of our cars he typically rents for the same reasons you are looking at as far as space ad gas mileage. He has rented minivans, crossovers, etc. and so far he has favored the minivan option (preferably the Town and Country) and continues to push me to get one.
Here is what he likes about them:
-You can haul a ton of stuff and still have lots of room for people
-You don't have to crawl over seats to get to the back
- You can easily move car seats in and out
- You can seat up to eight people in some of them unlike a crossover
-Your family can easily grow with it
- The gas mileage is fantastic
Now all that being said, I currently drive a Pathfinder that seats 7. I have no problems fitting all my kids in it (pregnant with #4). After driving some of his rentals, I must say the minivan is WAY easier and the gas mileage is unbelievable. I still haven't decided to make the plunge to soccer mom/minivan gal, but it sure has become tempting.
Good luck with #2 and your new car choice.