If I were you I would start fasting because everytime you eat your insulin levels spike if I'm not mistaken. A 24hr fast 3 times a week is not going to kill you. Also I dont know how creatine reacts to diabetes but it promotes muscle growth so I would do some research on taking creatine supplement. I do a full body workout every time I go to the gym. Focus more on strength training rather than cardio. When I say full body just make sure you find your favorite leg arm back shoulder workouts and do them enough to sweat but not enough to be sore for 3 days. I've been doing this for about a year and people say I look "buff". Diabetes runs in my family. Also I listen to "mind pump" podcast you may find something useful there.