Nah, there's a level in there somewhere where human population is stable and able to continue being creative and inventive, how cute is it when humans think they've discovered a new law of physics? Awww!

If you go higher they end up over-consuming the renewable resources such as fresh water. If you go lower the population ends up getting inbred or just dying off completely.

Also by managing the human population (and a small number of predator species populations outside the human zone of influence) the rest of the ecosystem manages itself quite handily.

Oh, have you seen what we did with Mars and Venus? The Venusian fjords are just chef's kiss.