To each his own.
I prefer to be locked up front and rear. There is no way I would do any kind off-roading without lockers. Open diffs is two wheel drive and that will not get you very far on practically any type of off-road terrain other than a flat gravel road.
Yes.... I've witnessed open diff Toyota pickups negotiate a nasty obstacle but not without some horrific wang'n and bang'n and multiple attempts.... too dangerous and too risky for costly damage and unnecessary carnage.
With open diffs in 4-wheel drive the slightest dip in the terrain where one wheel front wheel and one rear wheel is off the ground, you will just sit and spin tires. NO BUENO!
I did trail running with open diffs about 1 time and then immediately had a Detroit Locker and Trutrac installed! I installed lockers in my front and rear in my 85 before doing any trails.
Regarding Dual Cases – I ran a single MC case in my 85 and wheeled it for 10 years on the most difficult trails in Moab, California, Arizona, New Mexico, and Sonora Mexico. I didn't feel the need to be lower geared for the rock crawling I did. Regarding a hand throttle.... big pain in the arse and can get you in trouble quickly when fiddling with it while attempting to negotiate an obstacle.
ARBs and electric lockers have inherent issues with potential failure. An auto locking locker is practically failure proof, and reliability is very well known. Again, I never saw any excessive tire where in either one of my pick ups with lockers. There is some rear tire scuffing, but it is negligible.
Driving a vehicle with a locker installed in the rear diff does have inherent quirks. It sometimes clanks. It will stay engaged if you power around a turn, which will usually make the inside tire squeal. And yes, lockers in the rear and front diff will tend to “push” your straight and make in more tricky to turn. While this is normal, it's easy to get used to and control, even if you are a novice - and I have witnessed MANY novices on the trails.
If you are really concerned about the locker in the rear and it’s behavior on the street, go with a Trutrac or an ARB.
Just my experience...