Congrats on your new Jeep and welcome to the forums. If your talking about getting bigger rims, I wouldn't go bigger than the 17". Actually you might want to check out 15" ones instead. You can put bigger tires on your current rims but check out pro comp and crager rims. You have a ton of wheel size choices with any rim but the tire and wheel set could be more expensive for a 17" rim. There is a lot of info on wheel choices sizes here on the WF. Take some time to check them out and read up on it before making a decision.
Post pics when you do, we love em.