It was fun. the slide-in ranges were a bit redundant.
As for the hood with the controls built into them, I speculate they were eliminated because of the need to include so <span style="text-decoration: underline;">many</span> more parts in order to make that set up work.
AND
if they aren't installed correctly, its more liability on GE. Also, your limiting who could buy this. If someone has a cement or brick wall the stove will sit against, where would you put the controls.
I had a friend who had one of these slide-in stoves, from about 1965, in torquise with the control and clock module located in the wall behind the stove. When she finally replaced it in 1984 with a new slide-in GE range, the controls were mounted in the front of the stove and the module in wall was left behind, lest she be left with a hole in the wall.
I'm sure the idea was universality acrross all appliance manufacturers. That's what we have today. 30" stoves, 24" dishwashers, 28" wide frigs and up.