If you plan to have more than 1 more kid before you buy your next car (after this new one), then you really should consider a mini van. Let me give you my take, as I was hell-bent on having a big SUV when we were planning for our third child.
To seat more than 2 kids comfortably, with or without carseats, in an SUV...you will likely want one with 3rd row seating. Have you ever actually been in one of these? I really wanted one with 3rd row seating until I actually rode in one. In order to get to the 3rd row (in 99% of the one's I rode in), you had to fold down and flip up the middle row seat. Not such an easy task if you have a car seat strapped to that seat. I also did not want my older kids climbing over the seat backs, which seemed to be the only other option for them to get into the back. I also noticed that the cargo space was not much bigger than the trunk of my Ford Focus. Barely big enough to hold a full sized stroller, let a lone fit anything else in with it.
I reluctantly gave in when my husband brought a Dodge Grand Caravan for me to test drive. Let me tell you, it only took one time for me to realize that this was what I was looking for all along. Plenty of space in the front seat for mom and dad to not feel like we were sitting on top of each other. Two captains chairs in the middle row, with space between them to walk through. A full bench seat (fully capable of holding 3 adults/kid/carseats) in the back row. My cargo space is big enough that my double stroller can stand up (folded up obviously) on one side of the "trunk" and we can pile pretty much anything we can think of into the other part. I have grocery hooks so that my cans or whatever I have in grocery bags don't fall all over the place. My seats are movable and removable as well. For one trip we took (a 6 hour drive), we took out the captain's chairs and moved the bench seat to the middle row. We sat the 7 y/o and 4 y/o on either side, and the infant carrier in the middle. Never one complaint from any kid about space. Then we had the entire back half of the van to take our luggage and stuff in.
We are now awaiting the arrival of baby #4 and have no worries about seating arrangements in the van. The two older ones (8 & 5) sit in the back row on either side (with plenty of room between them so there is no fighting, lol), the 15 month old sits on the drivers side in the captain's chair, and new baby will sit on the other side.
I have decided I will likely not own another vehicle that is not a Grand Caravan. That is how happy I am with it. Oh, I almost forgot the gas mileage...I get about 25 mpg consistantly. I only pay about 50-65 (depending on the price per gallon) per week in gas, and I drive probably about 15,000 miles per year.