As the old saying goes, if it isn't broke, don't fix it. Just enjoy the jeep for a while, drive it, wheel it and then decide what improvements you need to make it more capable for what you want to do with it. We have folkes on here that do extreme rock crawling and folks that just do mild trail rideing and everything in between, one size doesn't fit all. If you just want to hit a trail once in awhile, you don't need dana 60's, both ends locked with 35 inch tires. So it's important to decide what you want from your jeep for the kind of wheeling you intend to do so as not to throw alot of money at it needlesly. I think any jeep could benift from a 2.5" lift, a good set of 31" tires, at least 4:10 gears and a lsd like the detroit true trac in the rear. As you get more experience and decide you what to get more hard core, then you can modify from there. More than likely the sugestions I have made will serve you well and give you a capable jeep, while still being highway friendly and very enjoyable without spending an arm and a leg. Don't over think it, you can spend alot of money on a jeep for parts you may not need. Take some time to get a feel for your jeep, enjoy it and go from there.
1987 wrangler, 258 I-6, 5-speed.
2007 liberty sport 4X4, automatic
2009 ford ranger 4x4 FX4 OFF/ROAD, 5-speed