I'm in a similar situation. I'm pretty active and exercise a lot, which makes me incredibly sensitive to insulin. I've had Type 1 Diabetes for a year and a half now and I'm 20. At first I was using 1 unit of novarapid for every 10 units of carbs and 12 units of levemir once a day.
After a few months of learning about how exercise and food affect insulin sensitivity, I now take 1 unit of novarapid for every 50 grams of carbs , which usually means I'm only taking 3 units of novarapid per day and no levemir. I was worried that I was taking too little, but after reading a lot online, it turns out that people who have very low levels of insulin in their bodies generally live longer, age slower and have better overall health. They also have less triglycerides in their blood, which is great for your health and high insulin levels might be a cause for high blood pressure.
This site has some good info: http://www.healingdaily.com/detoxification-diet/insulin.htm
I also find that even on 3 units of novarapid a day and eating about 160 grams of carbs and 200 grams of protein a day, it is still too much insulin because I hypo sometimes. I have tried days where I just use levemir, but I feel like I am more constricted to eating at certain times of the day, as my sugar levels are constantly dropping, whereas with novarapid after 5 hours it is out of my system, which means I don't have to constantly eat to keep my sugar levels normal.
I think one of the most important things for Type 1 diabetics is making sure your insulin sensitivity is high, so you don't have to take a lot of insulin and therefore never really have high sugar levels, because when you do take insulin it always acts fast.