Hey, could fix problems 2 and 3 right there! The intake and use of oxygen as fuel has been integral to the way our bodies operate since forever, so perhaps the more lungs you have, the better/more efficient the base attacking organs is and the faster certain other things can do their stuff.
Thanks for the idea, that's actually quite in line with what I had in mind! I've been thinking about evolutions that increase every organs health/regen/resistance(to contact damage) per every lung you have. So that you would have a reason to make at least a few lungs even if your air production is so reliable that you don't need extra air storage.