If you render to linear gamma, 32 bits, you will get as much dynamic range as you can possibly need. Also, if you render to the picture viewer without specifying a save location, you can go in after the fact and do your color/tone grading in the Picture Viewer. You do that by going to the filter tab at the right and checking the “Enable Filter” box. Then you can adjust saturation, brightness, contrast, exposure gamma, and even RGB curves.
Once the image is to your liking you can File>Save As. Just make sure you choose Animation or it will only save single frames.