I went with the Quadratech Folding Hitch, which will accommodate up to 4 bikes. It allows you to fold it down out of the way to open the tailgate without completely removing the hitch and it'll clear a bigger than stock tire. That way if you want to leave it on the Jeep full time, you still retain access to your trunk. But on those occasions when you have bikes mounted on it, you have to remove the bikes first before it can be folded down.
As far as I know, the only way you're going to get access to your tailgate without taking your bikes down each time is by going with a spare tire mounted system, (assuming your spare is still mounted to the tailgate tire mount).