Welcome. It sounds like you have a lot of interesting plans for your KJ. I'm just getting started with my KK but one thing I can tell you from experience, I have an ARB bumper on my TJ Wrangler and it is awesome. A few days after I installed it, a pickup truck lost control on ice and hit my bumper at about a 30 degree angle off of head on. The center of the pickup hit the driver's side corner of my ARB bumper. The pickup looked like it hit a telephone pole. Its grill was destroyed, the hood was buckled and the bumper was pushed in several inches right in the center. when I got out and looked at my bumper, I was amazed to see a small scratch and dent barely bigger than a quarter. I was able to take the bumper off and pound the dent out with a hand sledge and now you can't even tell. I have had it about 10 years and been completely thrilled with it.
I have no direct experience with ARB's Liberty bumper (they don't make one for the KK), but the brand is definitely good. From reading the forum, it is also apparent that there are several other great bumpers avaialble including the one from Rock Lizard that Digger mentioned. Everything I have read about Rock Lizard products is top notch and there are a lot of forum members that praise them. Unfortunatley I don't have first hand experience with any RL products (my loss!). I understand he is shutting down his business soon so you'll need to order soon if you want one. I'm sure there are other good ones but I'm new to the forum also and haven't read enough to mention others.
Welcome, and happy wrenching!