A 2011 truck on original shocks probably should get new shocks. Your hitch will affect the ride of the combined vehicles. We have a 27.5k Reese hitch and I do get a big of chucking sometimes. I'm seriously thinking of getting a Reese Goosebox so that I only need a turnover ball in the bed that's easily removable.
Also look at the yellow sticker on the driver's door that tells you what your payload is. Then take a look at the GVW of whatever trailer you're considering and add 20% of it's GVW to the payload that you'll be carrying. Add to that the weight of passengers, supplies, etc., to arrive at your total payload. You don't want to go over.