3.73's are great for track/road use. I don't personally have them, but a friend of mine has them in his 06'. They feel awesome. Personally I wouldn’t get 4.10's or lower unless I was on the track all the time.
You start with 3.55's so it won't be a big difference. I believe there are some 3.90s out there of a non-Ford manufacturer. That may be the best of both worlds.