I have an 08 JKU and we fit 2 adults and three kids (5, 7, & 9) very easily. We have one of the Radian car seats in the middle for the younger one and boosters on the sides. We had true carseats for the other two for awhile and they fit fine but they have outgrown them. I would suggest the plain Radian, like
this one, for the middle as it is narrower and allows for a better fit. Plus if you aren't familiar with the radians, the owner's child was killed using a regular carseat design, so they designed these, they have a steel frame and full back and are much safer, and well worth the investment.
We routinely go on long trips, Colorado, Florida, etc. which are 17 hr trips for us. Camping trips were a little cramped because of the amount of gear you need for 5 people, but I had an offroad trailer for a while to haul the tents and stuff and recently moved up to a popup so no worries now. Yes you will have more room in a bigger vehicle, but you can make it work and be happy with your daily driver as well. Nothing like driving into work with the top and doors off.
Just FYI I also have Jeep Commander that has the third row seat, more storage space, etc., that also serves as a good family vehicle but the only reason it gets used instead of the wrangler is if we need to haul more than 5 people, or I need the storage space on top of the vehicle. This can be solved with a rack on the Wrangler if needed.
Cheers!