That is exactly the Highlander I have, but do be sure it actually has the factory tow package. Its not realistically possible to install it aftermarket, there is an oil cooler that is part of the oil filter assembly that would cost a small fortune to retrofit. You can have any Toyota parts dept check the VIN to be sure. You will also need a receiver which can handle a weight distribution hitch, and of course a brake controller.
The limiting factor on my rig is the tongue weight. I have dual golf cart batteries, a pretty heavy mattress topper, and travel with a full freshwater tank, so I'm around 550 on the tongue. The 191 looks to be a little lighter overall and on the tongue than the 179 is and if you're not boondocking a lot your tongue weight will be much less of an issue. But you will still want a wdh with sway control I think. It will end up with a pretty fair level of tension on it. I have a 1200 lb one which is overkill, I'd get a 600 lb one if I didn't boondock, and I'm thinking of changing to an 800 lb one for my requirements.
I've weighed the rig and each axle and I'm well within all the axle limits and gross combined vehicle weight rating. I've driven my rig all over the Appalachian mountains on the WV two lane roads in sun and rain and never felt stressed about it (except when I first got my used trailer and my trailer brake shoes were disintegrating and causing wheel lockup-nothing to do with the tow vehicle). Ditto with driving it out here on the OBX with pretty extreme winds from all directions. I use sport mode for engine braking whenever I'm on more than about a 7-8% grade, which puts me at about 50 mph, and I keep my speed down to 60 on the freeway anyway to save fuel and run at about 50 in high crosswinds winds, say 35 mph or more. I get about 14 mpg towing on flat ground with no wind at 60 mph. That won't change much regardless of what tow vehicle you get as long as its got a modern drivetrain. The fuel tank is just under 20 gal so I can go around 180 miles with a reasonable reserve. Three hours and I need to take a bladder break anyway.
Overall I've very satisfied with the Highlander as a tow vehicle. Many on the forum would feel its undersized and I do agree that I wouldn't want to go any lighter for the big rPods. It works for me because the 90% of the time I'm not towing the vehicle is an ideal size for my needs and very comfortable.
Hope that helps.
Edit: the trailer axle is NOT well within limits, its marginal, but that's the way they're made, not a tow vehicle issue. There are multiple threads on rPod axles on the forum you can search through on that if you're interested.