The divertor for the ITER tokamak fusion experiment looks to me to have a very small size/volume given the energy flux it will likely have to handle. One could reduce the heat load by a factor of two by making the device cross section up-down symmetric. One could also limit the experimental shot duration. Magnetic hairpin limiters* could be added. All such redesign will be costly and time consuming.
*See L. Nuovo Cimento, vol. 42, pg. 421, 1985