Well if you dare to grow nectarines (really hard to grow because of insects and fungi)
I can suggest one that exactly fits your needs. It has acid, but not too much, just enough to enhance flavor. Sugar is high too, it is a white, but you can’t really tell it’s a white. Neighbors thought they were plums.
Arctic Glo Nectarine
If you want even more acid, well Indian Free Peach has ton’s!
