How about a regional that is a mandatory 5-year employment contract. After 5 years you are no longer employed by the airline and must leave. If you leave early you must pay $X to cover your training bond. All compensation is paid at a flat salary, doesnt matter how much or how little you fly.

Year 1, you are paid $40k, and sit right seat
Year 2, you are paid $45k, and sit right seat
Year 3, you are paid $55k, and spend half the year in the right seat/half year left
Year 4, $65k left seat
Year 5, $75k, left seat

This would guarantee movement, and all but guarantee you will have 1000 PIC turbine at the end of 5years. At that point you could go where ever you wanted without having to worry about a quick upgrade in hopes of building PIC time. The people who are most eager to fly are those newhires trying to get 1000 SIC turbine, and the newly upgraded CAs trying to get 1000hrs PIC turbine. This would benefit both the pilots and the company because everyone would want to be productive and fly as much as possible so they can get their hours.