Yes, it's good for blood sugar. Hard to tolerate just by itself, best to add to something. I sometimes add it to scrambled eggs! Adds a nice flavor.
Some of belly fat will be directly impacted by low carb, at least that's MHO and experience. When I go off low carb I actually refer to my developing belly as my "carb belly," and it responds pretty quickly to low carb. Planks are good for abdominal area and easy to perform.
One of the oft overlooked exercises for strong abdominals that I used to teach many years ago was simply getting in the lifelong habit of NEVER getting up from a chair or couch using your arms. Lean forward and use your legs and abdominal strength to stand up. Not only does it develop your abs and legs, it keeps them strong for later on in life. I remember reading something years ago that a large percentage of people in nursing homes are there for no other real reason then they've lost the ability to rise/get up by themselves. Keep those abs strong!