The situation with couplers on my layout may appear to be getting a bit chaotic.
I use three link couplings on fixed rakes of short wheelbase 4 wheelers, because if you have any tight curves, say less than about 30" (750mm) radius and you propel the rake in a shunting move, long wheelbase vehicles will tend to lock buffers with short wheelbase ones. For uncoupling I use a penlight with a thin steel wire hook, the stem of which is reinforced with a piece of fine copper tube taped onto the body of the pen light.
Using Kadees on the end vehicles of rakes is a good idea as it allows you to change locos in hands free mode. There are a couple of reception loops in front of my station and through goods trains often draw up there to change locos. Because a goods yard or marshalling yard for a mainline station would take up far too much room I don't have one, and so I rarely shunt goods stock. The three link couplings have stayed coupled up in my fixed rakes of wagons for literally years. My hand built goods locos have three link couplings as well because these look best. If I want to run a proprietry loco which has Kadees or tension lock couplings, I use match trucks.
The carriage rakes have Kadees at the ends to facilitate hands free operation and I can change locos at the main up platform (York 8S) using a Kadee electromagnetic uncoupler. The non-passenger carriage stock has Kadees and I shunt these in hands free mode at the back of the layout (Queens Street Sidings), using magnetic uncouplers. I also have two rakes of loco coal wagons (one full, one empty) with Kadees at the ends that are shunted up and down the ramp of the coaling stage and exchanged, by a tank engine, all in hands free mode. (Yes, I know that there was no ramp and no coaling stage at York, but I have created a mythical York(South) shed based on the old Loco Works No1 erecting shop).
Colombo
