If I look too carefully, I see a slightly contagious, very mild, and benign form of insanity.
If you see suffering everywhere you look, the real problem may be in your way of seeing things.
But since suffering (in this context) is an essentially subjective thing, you can't go mixing it with an objective measurement like kilograms and make it more objective. Drawing up a "suffering per kilogram ratio" is exactly as subjective as simply asking whether cows suffer more than fish in the process of becoming human food. It isn't useful to anyone, except possibly those who published the ratios, being little more than an organized expression of their opinions.
The implication I draw from the very existence of a suffering/kg ratio is that those who invented it must believe that there is an acceptable level of suffering that any one person may cause, and that ratio may be a useful tool for staying under that threshold. That's like starting every morning by swearing into the mirror that you won't make any more than two people cry today. If it really is valuable to you that you don't make people cry, why wouldn't you say you don't want to do that to anyone, ever? It may be inevitable that it happens, but a practically unachievable goal is still a goal.
"...those who invented it must believe that there is an acceptable level of suffering that any one person may cause..."
I'd suggest that quantity is one thing to put into the multi-objective optimization problem we all are unconsciously solving. If you choose to interpret it as a threshold, that's OK, but others might treat it differently.
In particular, your construction of "won't make any more than two people cry today" is pure straw man based on your invented threshold rule.
Here's a different analogy. The speed limit on my drive to work today is 65 mph. I drove 70 most of the way. I don't have a hard rule that I can go at most 5 mph over the speed limit, but I do look at [my_speed - limit] as a factor in my driving, and try to keep this difference reasonably small.
But do you consider "reasonably small" in relation to the magnitude of the posted limits? Do you drive 30 mph when the posted limit is 25? If not, you might be interested in "speeding ratios".
But in order to really fit the speeding analogy around animal suffering, you also have to live in a world where speedometers and radar measurement devices don't exist. You're speeding if anyone thinks you might be going faster than the limit, even if nobody can really know for certain.
We don't have any animal suffering meters, or posted limits. We know a limit exists, but we apparently don't know where exactly to draw the line. Clearly, a puppy mill that abuses its livestock and runs pit fights will get the operator thrown in jail. But a battery farm that slices the beaks off of chickens and crams them into cages too small for them to stand in will get ag-gag laws that protect the owners from both punishment and scrutiny. Dogs are cuter than chickens, and less marketable as food, you see. In that world--the world we live in--a suffering per kilogram ratio is just pissing into the wind.
If you see suffering everywhere you look, the real problem may be in your way of seeing things.
But since suffering (in this context) is an essentially subjective thing, you can't go mixing it with an objective measurement like kilograms and make it more objective. Drawing up a "suffering per kilogram ratio" is exactly as subjective as simply asking whether cows suffer more than fish in the process of becoming human food. It isn't useful to anyone, except possibly those who published the ratios, being little more than an organized expression of their opinions.
The implication I draw from the very existence of a suffering/kg ratio is that those who invented it must believe that there is an acceptable level of suffering that any one person may cause, and that ratio may be a useful tool for staying under that threshold. That's like starting every morning by swearing into the mirror that you won't make any more than two people cry today. If it really is valuable to you that you don't make people cry, why wouldn't you say you don't want to do that to anyone, ever? It may be inevitable that it happens, but a practically unachievable goal is still a goal.