Normal SuperFlat is only 3 blocks deep I know that's not deep enough for most builders so I made a simple mod(not really simple mod anymore at least to me)
that adds SuperFlat32, SuperFlat64, SuperFlat128 to the world Type button.
New version released i have added a block type feature that allows you to show what block the superFlat world types uses (includes the normal superFlat).
You choose what block you want on the create world screen under "more world options" its called "Block Type:".
Don't worry the world saves know what block type its using.
http://www.minecraftforum.net/topic/943697-11-superflat/
Derp.
Reegareth 1 month ago