I live in NJ and have all kinds of weather issues... I use sand in my run which works best for me... You need to find out what works best for you...the sand makes it easy to rake. water...poop...snow...ice...are absorbed very quick...i just replace the sand i take out once a year...
I would say she is a Hen... From the comb and waddles along with the tail feathers, she looks like a hen to me... I have several hens who are also aggressive towards roosters..
I also had a snake problem...I live in the North East and have Black Rat Snakes.. They are great rodent control, although a large Rat Snake killed one of my broody hens who would not get off the nest box.. I had to rewire my entire coop....