I agree with Mark, the 707 is not as fast in pitch trim as the 727. The 2D autopilot seems to work pretty well. Use quick taps of the mouse button on the pitch wheel up or down, and watch the pitch change on the horizon. With short taps on the pitch wheel I find I can control the pitch pretty well.

If your problem is the elevator authority, a force feed back stick, as CoolP said, will help make the force a bit more realistic.

Lou