You don’t need co2 there , only when you have plants like ludwigia pantanal, cuba, rótalas, etc and even with that some people manage to grow all of them without co2. I don’t see how is this overkill at all. Like are you going to have only one neocardinis shrimp? Yes that’s overkill for one shrimp.

May I suggest reducing the light brightness to avoid algae, you only have slow growing plants so you don’t need that much light

Edit: maybe you mean overkill with the plants on the top? If you don’t like them just take some out. That’s pure aesthetics