Bryan,
Don't know if you have made your purchase yet, but I have a 2017 Jeep Grand Cherokee Trailhawk with the V8 engine that I am currently building out.
Obviously, I'm biased, but it's a great vehicle (although so is the 4Runner). It has great highway manners and the big V8 just eats the miles. Very comfortable to drive in for long periods. Much, much more comfortable on the road than a JK/JKU.
Almost anything is going to struggle to keep up with a kitted out JK on a pound-for-pound or dollar-for-dollar basis, but the Trailhawk (even stock) provides a pretty stable off road platform. Only you know what you'll be doing with the vehicle, but there's plenty of capability there.
Also, from the photographs it looks like the Jeep has rock rails already on it. That is a huge plus with a WK2 Grand Cherokee. They are difficult to source and depending on the version/brand you go with will cost you between $800 and $1,200 (unless you find second hand). So that's a nice bit of value already on the vehicle.
If I can answer any questions let me know... I'd be happy to help where I can.
Vin