The "perfect fit" does not exist and fitters know that. The point of getting a fit is to have a foundation from where to make little adjustments as necessary. You are a special case. But seriously if you have only had the Treck for 5 days now that is not enough time to evaluate it. I just set up a new Treck cyclocross bike and I feel like I am riding a tank but I know in time I will learn its way and make adjustments as necessary.

With your knee condition and if you had a little bigger budget you may benifit from a custom frame. Just an idea...