Change world elevation higher?

[lmv0]

Please change the elevation of the skylands world higher on generation. Instead of generating at around y=64, generate at y=100 to 120 or something like that.
This creates a few positive side effects, namely no ugly black voids and the clouds being under the terrain instead of above. Upon updating, check for the current elevation and then move the world higher in case of using an older version that still generated around y=64. The black void completely ruins the otherwise amazing generation.
Worlds are big now anyway (256) and I don't see the reason why someone would build an 100+ block high tower. Make this a config setting?