A dramatic way to change your place's appearance would be to convert to a different style roof. However, doing so may cost more than you're willing to spend. Also, a few things visible in the photo will result in additional costs--there are 3 overhead power lines visible, and they may be a reason for a low-slope roof being used in the first place (lack of adequate clearance). Power company may want a small fortune to relocate them, on taller poles. The other thing is the chimney--it will also have to be extended upward.
Maybe you should just be happy with what you have--place looks pretty nice to me.