CVT Mt. Shasta (with bedding and memory foam topper inside), along with 2 full MFC fuel cans, 1 full MWC water can, a tote packed full of recovery gear, a Hi-Lift, and a homemade-fabbed up front roof cage all attached to the stock roof rack with no issues ta all. Fully tested, among other adventures, on a 6000km road trip to through 6 state last year (to Colorado and back), on freeways, mountain highways, crosswind laden Wyoming plains, lots of offroad (off camber, steep, rocky stuff on the Alpine Loop) and again, no issues at all.
I weight 200, my Wife about 140, plus two dogs totaling another 130 pounds, and we all sleep up in the rooftop tent. I've noticed no integrity problems with the RTT supporting that weight at all. Now, at some point (likely next spring) I will be upgrading to a larger sized rooftop tent, purely for more usable space inside. And at that time I will probably upgrade to an aftermarket roof rack (like a Gobi or something), but for now everything is working tickety-boo.
I initially upgraded the stock suspension to a simple "add-a-leaf / spacer lift, but once I realized a rooftop tent, and bumper, and winch,m and all the other necessary additions were in my future, I full upgraded to an Ironman HD suspension (very similar to the OEM packages) It came with huge heavy duty rear leaf packs which amaze me at the load they can handle, right now they are on the highest (stock location) setting on the adjustable rear shackles, so when I (eventually) add a rear bumper I still have room to adjust the ride height