I am in no means trying to insult you.Your roof is NOT a DIY'r friendly roof.It is very steep and it is very dangerous for you to attempt any repairs yourself without knowledge of walking a steep roof.
IMO you should call for a roof inspection from a professional.Many homeowners every year are seriously injured or killed by trying to perform repairs without knowledge or abiding by necessary guidelines pertaining to fall protection.
I am not saying you could not do it.,I am only trying to direct you with safety being first and foremost.
You need to learn how to negotiate such a roof and also understand your equipments intentions and also its limitations.
But yes your roof has a couple of issues but a first hand inspection would determine if you will make it through the winter.