Stack Belts...but with different types of items in a stack

[FactorioParadox]

What ?

Basically, the stack belts mentioned in Friday Facts #225 (https://www.factorio.com/blog/post/fff-225), except you can have more than one items per stack. In other words, sushi belts taken to the extreme. Some additional changes would have to be made, such as Inserters having an option to only place items on existing stacks, not to mention that inserters would have to be changed to handle multiple different items at once.

Belts being able to handle multiple items as well as the option for an inserter to only place items on an existing stack would be researched as part of Logistics 4, which would have a prerequisite of not only Logistics 3 but also Stack Inserters because they are kind of necessary for this and Automation 3 for balance. Like its prerequisites, it would require red, blue, green, and purple science.

Why ?

I feel that this would not only buff belts but buff them in a more interesting way than simply increasing throughput by allowing items of the same type to stack and would open the doors for a whole slew of interesting designs that may very well rival bot-based setups in many ways but not to the point where they are basically equal in all aspects.

[Engimage]

I am strongly against the idea of stacking different items.
First of all you just can't visualize this in any meaningful way.
Second this will require so much additional memory/CPU to hold this data. It is basicly like replacing every belt spot with a chest which is rediculous.

I think these 2 point are enough to not even think about such an idea.