Sounds like a real nice truck. Here are items that come to mind.
1) Exhaust Manifolds: Expect the exhaust manifolds to warp. They warp after so many heat/cool cycles. In fact, if you wanted to do yourself a favor, you might remove them around 'now' time-frame, and have them belt-sanded or machined ...before they break the head bolts (then it's a much harder job). Don't buy new manifolds, they'll just eventually warp in the future. Get the ones you have machined or belt-sanded smooth ...they won't warp again once warped.
2) Hemi-tick: You're not out of the woods. Some hemi-tick might be exhaust leakage from warped manifolds. But the more chronic 'tick' might or might not happen. Use good oil like Penzoil Ultra Premium Synthetic, or another real good oil (people say). And just enjoy the truck. That can also help prolong your lifters (next item)
3) Roller Lifters/Cam problem: Use good oil and just enjoy the truck. Most owners never have a problem. Some do.
4) Electronic Power Steering Ram Failure: This seems like a new thing happening where the EPS can flake out. Expensive to replace. The control board area on the EPS rack seems to get water/moisture in it. How to avoid: Make sure all tie rod boots are firmly in place so no water can intrude. Avoid driving in water ...cross your fingers. If you have an issue, remove the square cover and see if there's moisture in the control board area. Try drying with a hair dryer ...and seal the cover back on.
5) Rust: If it's been driven in salt ..or you plan to drive it in the winters, definitely get it undercoated as soon as you can. The rockers/box wheelwells/cab corners/tailgate are well documented rust areas for the rust-belt guys. Even the middle of the front fender too. Wash off, under and around regularly. A guy I know, his 2013 is showing quite a bit of unsightly rust-through.
6) Seat Cover: Getting in/out of the truck tends to wear out the edge of the driver's seat cover. There's a pretty stout metal bar around the perimeter of the bottom seat cushion. If you can install some sort of step or running board and train yourself how to get in/out w/o putting strain on that area, it can prolong it's life. If you have to replace it, buy a genuine Mopar seat cushion. I bought an aftermarket one, it was super stiff. Then bought a Mopar foam bottom. Definitely OEM quality is the way to go.
7) Wierd Dash Light and No start: The TIPM (computer) seems to need real good and clean battery power. Weak grounds or dirty cable connections seem to cause wierd issues on these RAMs. Seen it myself on my own vehicle. If your truck suddenly won't start or you get a lot of wierd dash lights and messages, the first thing to look for are batt connetions and your battery condition. Not just voltage, but a load test. The fix: Make sure your truck has a good battery with clean battery terminal. And the engine/body grounds are good.
8) Traction control/4x4/Brake dash lights: These come up from time to time. Usually on higher mileage rigs. Often a failed wheel speed sensor or damaged speed sensor wire. The brake switches can fail too. But usually after many many miles. But if you see these dash lights, don't panic, get your computer scanned for codes.
9) Misc: The rest of the issues that come to mind are just general things that can happen to any vehicle: HVAC vent actuators, upper ball joints, wheel bearings, etc. I wouldn't worry much about them unless they fail.
10) Tranny: What transmission does your truck have? 8-spd or the Mopar 6-spd? There's nothing wrong with either transmission. But the 8-spd changing/checking the fluid is another matter. 6-spd is easier to check/service. Just something different to get used to if you have the 8-spd. Make a note when yours should be changed. (not yet).
Overall the trucks are solid. Don't take the above list as a list of for-sure weaknesses. They're just things to be aware of and stay cool about if you see them. Hey, let's see a picture of your truck!!