If we throw out the retrievers, I’d probably pick a Deutsch Drathaar, they have all the bird dog qualities and can also handle fur/trailing. Specifically talking about birds, I think some sort of wirehair pointing breed would win, because they can stand up to cold late season duck hunting better than a spaniel or setter would. I’m not sure you could call that “low key” though.
My Boykin will retrieve well but will occasionally get half way out and then turn around and come back in exceptionally cold water, and on those days I have to keep hunts very short after he gets wet. A lot of natural drive that made up for training mistakes on my part. With no training on it, he also does an acceptable job quartering and flushing. Pretty rare breed outside of the southeast apparently, I hadn’t seen one or heard much of them until we moved to NC.
