So I have been towing for years and I tow a car hauler with various cars on it a few times a month in Texas so it's mostly flat highways. Towing, it does fine but I am sure I am right at the limits of its capacity and that worries me sometime. It sags in the rear, but it pulls straight. I get 10 miles per gallon and we know the Land Cruiser is reliable, but I'm always on the hunt for the next best thing and even though I really don't need it would a pick up be better since a longer wheelbase? Will it be safer on the road? I only pull at 65 miles an hour so speed isn't an issue I haven't felt any hairy moments whatsoever. Should I add to my fleet or just continue with the status quo? 
Wheelbase is your friend when towing. A longer pickup truck will likely give you a less stressful towing experience and possibly even at higher speeds, but if you haven't felt uncomfortable in the Land Cruiser and don't plan on towing anything heavier than what you've done so far, you might just want to do a sway controller to be on the safe side rather than upgrading your tow vehicle. I went from towing with a Nissan Frontier to a 2015 Silverado this year, and the extra capacity of the bigger truck just makes the whole experience a lot more relaxed and enjoyable. Lots of people will tell you that you can tow X with a 4 cylinder Ranger across the Rocky mountains, and I'm sure you could, but at no point will you enjoy that drive.
