Not sure why your 13 JGC isn't worth much on resale. Mine, an Overland, is in great shape (many, MANY shop visits over the years), and the dealer continuously sends me offers to buy it back. Not interested as I enjoy not having a car payment. ~96k miles and it's just starting to have issues with burning oil. Good thing I got an extended lifetime warranty with it as it's already come in handy several times.
I almost bought a Toyota 4-Runner when I decided on the Jeep. Wasn't very impressed by the Highlander at the time, but I'm sure they've improved it significantly since 2012-13.
My '13 JGC has 140,000 on it. Nothing wrong with it, it's just that it's the Laredo model, though it has the premium rims, UConnect, leather seating, heated seats and all the stuff the Limited has. I'm the 2nd owner, bought it as a 3yo with 32,000 on it. Paid just over $21k out the door for it so I'm not complaining about the resale value that's left. I've gotten my money's worth out of it.
Mine doesn't burn or leak a single drop oil. I've run full synthetic in it since I bought it.
Personally, I'd love a 4Runner but don't want to spend that kind of cash for a vehicle. The Highlander seems to be a capable vehicle, it'll never leave the pavement (neither did my JGC) I just really liked the ride comfort, handling, amenities and the power of the 3.5L V6 they put in it. In many ways it reminded me of my JGC when it was newer.