You may just want to get a $2,000 frame and move your components over.
I've been riding carbon for the past 6-7 years. I started on a $3500 bike (Kuota Kharma w/Ultegra) and am now on a Leopard DC-1 (moved my components over). The Leopard is almost as good as the Kuota. I figure both frames are $2,000-ish, with the Ultegra being $1,500 or so. In my experience shopping, purchasing & riding, there is a difference between $2,000 frames and $1,000 frames.
I ride a 60cm, am 6'3" tall and 260 lbs.