Stick with 33's and you need to go for 4.88 with your 2.5L engine and 5-speed transmission combination. That's the ideal ratio for your Jeep running 33's.
Your 2.5L engine means your rear axle is a Dana 35 which definitely (!) is not strong enough for 35" tires. 33's are the absolute upper limit. Not to mention your 2.5L couldn't turn 35's very well since the lowest gear ratio you can install into the Dana 35 is 4.88 and that ratio is only suitable for 35's with the 4.0L engine.
The biggest problem with 35's on a Dana 35 is what you'll see here...
http://www.billhughes.com/dana35c/. And not all of those are even 35" tires... lockers and getting too aggressive on the trail can break the Dana 35 with even smaller tires if you don't respect its limitations. But for most people, the Dana 35 holds up with 33's so long as you don't also install a locker and don't get crazy with it.