I have not done any of these. I have done more than half of my RR of various brands. It starts with getting the car to sit at the correct height or where you're happy. If you set a standard height for your cars, mounting couplers gets easier. You don't have to change the height. You may just need extra shimming.
I personally don't like how the offset couplers hold up in big trains. They can dip (or raise), and bow out. So I use standard ones and shim appropriately.
Always look at the end weight of the car too. That way you can place it anywhere in the train without worry.