I was just searching for a mod that does this. I have most of the deadlock stacking addons installed and am playing with Deadlock Stacked Recipes and I was wondering why there was no stacked mining mod. I hope the idea is not dead.
However, I don't think stacked ore patches are the way to go. Changing the map gen for this seems unnecessary. It would be enough if we get a new miner that outputs stacked ore but with a reduced mining time, to keep the actual items mined per second the same as vanilla miners.
About the problem of reducing the patch by the correct amount, maybe handling it like Reika's mod "DirtyMining" would work.
Another question: the main reason why I was looking for a mod like this, besides convenience, is UPS improvement. Is it even more UPS efficient to run a 10s recipe combared to 10x 1s recipes?
Thanks for your mods and I hope there will come a day where we will have a Stacked Mining mod.