To the OP: For a DD/mild all around wheeler, I wouldn't put a cage in it.
...,if you can move enough to hit the cage with your head with your seatbelt on - even by trying to wiggle out of it - wear a helmet if you're moving. It can and will SERIOUSLY injure you in a rollover. Best of luck to you and don't skimp on safety.
This can't be stressed enough. There's very little side support in the stock seats. Everything in the stock Jeep is plastic or padded. Any metal you add will be closer to you then the current interior. You really don't want to wang your noggin on a cage bar. Without a seat/harness that will hold me in place, I wouldn't put the jungle gym in there.
Having said that, if i were going to cage my wagon, my minimum build, and why:
6-point cage.
Full "B" hoop mounted behind the rear of the front seats(about the middle of the rear door on a 4-door)
Front down bars, through the dash, as close to the A pillars as I can get them. Straight spreader bar at the upper windshield corners. One diagonal bar from the left windshield corner to the right B pillar intersection.
Rear down bars from the B hoop to the load floor.
This setup would do away with the rear seat.
The reason I'd call this my minimum is because it would support the front roof area in a roll-over. Seems like every SUV that turns over always crushes the roof.
B-hoop so far back to get it away from my head.
I'm not sure about running bracing to the upper seat belt mount on the A-pillar. The only hit I've taken inside my XJ rang my head against that seat belt mount. Not sure I want exposed metal in there.