Hba1c of 6.2 is considered acceptable for persons with type 1 diabetes by most doctors.
However, hba1c gives you an average blood sugar of about 140. Consider that people without diabetes will have an a1c of < 5.0 and an average blood sugar less than 100.
It is also known that permanent damage can occur when blood sugars are above 140. Ideally you will use diet and medication to get your blood sugars as close to normal as you safely can, and this includes avoiding swings both high and low (stable blood sugars is also important).
It would probably be good for your health if you can work to get your a1c below 6.0.
I find low carb diet is very helpful because it means I need less insulin and also blood sugar swings are less.