Hi
@kitedoc
I suggest you have a good google around the
Insulin Index of various foods - including the proteins.
You will see that different types of protein (beef or white fish, chicken or pork, hard cheese or tofu) have different places on the insulin index charts.
Therefore, the choice of type of protein carries a different insulin requirement, and this is possibly where
@Mel dCP 's insulin requirements differ from your need to allow for 50% of protein.
I imagine that by selecting proteins with lower places on the Insulin Index, you could reduce your insulin requirements - but it would be a very trial-and-error personal thing, with lots of testing involved.
In the past, I have seen a magnificent chart showing the Insulin Index of nearly every food known to man, all sub divided into food groups for easy comparison. But I am afraid I didn't keep the link. The link I will include below is a v basic one, and I haven't looked at the site in depth to see if it is a good one.
https://optimisingnutrition.com/2015/03/30/food_insulin_index/
But it should give you an idea of what I am talking about.