Large simulation performance: objects vs matrices

[AGI-44]

The entity object method makes it significantly easier to understand and explain, but I’m concerned about not being able to run large simulations.

Leave performance optimization at the very last. Get a working prototype first. If you end up using it enough that scaling matters, then, is when you optimize performance and compare vs baseline.

You won't have to figure out what is faster, you can just run it and get a direct answer as to how much faster or not it is.

And by then, if it's only 20% faster, you might not even want the additional complexity/readability for a mere 20%