An auto locker, any type, is great up front even without locking hubs. As said earlier, it's not great in an environment where you'll be road driving in compact snow and ice. Rear units are fine but not front.
That said, I'd never put an Aussie/Lock Right or EZ Locker in a rear axle. The reason? They wear. Unlike a full Detroit, the lunch box lockers (except No Slip) all wear every time they unlock to corner. The only exception would be if this were a temporary application. Then I'd just recommend cheap.
Selectable lockers have their own issues. If you're concerned about steering being difficult with an auto locker up front, you're going to hate a selectable. Yes, unlocked they're easier, but locked, much harder and frequently a steering pump/box upgarde is required.
Mentioned earlier was debate on if you should modify your D35. My vote is NO!!! You'll get people in here telling you blah blah blah mine has worked for years..... The fact is, if you continue to wheel you'll upgrade your axle. Don't add money to something that you'll never be able to recover. Have you ever heard someone regret doing a 44, 8.8 or other instead of keeping their D35? You'll hear lots of regrets on this board but you won't hear someone say that they wish they had kept their Dana 35.
In the end, there is no perfect system. You just have to work with your own budget and talents. Don't waste your money. Make a plan, save your money and do it right the 1st time. The 2nd Jeep is always easier to build because you know what pitfalls to avoid. The 1st Jeep can be done without too many mistakes if you know where you want to go with your project. But, knowing your long term goal is crucial.