Re: scaling up is the answer?
Talk on JET at the IET last night.
Power out/Power in is "Q". Jet manages a Q of around 0.6. ITER is targetting 10. But this is just the plasma power in/out ratio. It ignores the power used by the excitation systems and, of course, losses in energy extraction for Useful Work.
For a commercial system, you need a Q of 30. So ITER is the next step on the road towards that. But it won't get there.
The Stellerator is the interesting shape you describe. The (quite believable) view of the tokamak guys is that they will be very difficult to maintain given their shape.