Rough that you're being downvoted. I'm not vegan myself because I can't help but think if the rolls were reversed and I was the size of a shimp and a shimp was as big as a person that fucker would eat me in a heartbeat.
Why? It just sounds like you are setting up your followers for a world of hurt. The situation might align nicely with the rules at this moment but situations change.
One thing about Buddhism is the rule restrictions on food for the Monks is to go with the food of the area. Don't demand special food and don't refuse what others around you are eating. Which seems sensible enough.
How does eating goat vs shrimp reduse animal suffering? A goat is a lot more intelligent and social and has feelings. The dumber the animal you eat means the less misery. For example short of starvation I would never eat a primate.
Really not seeing your point of view here. Rules that are arbitrary by pure chance are going to get you what you want and this is good as opposed to rules that get you what you want.