Random ore veins

A large part of the Caves and Cliffs update was to make mining more interesting. This was largely fixed. However, one problem remains. Ore generates within certain y levels, with unique 'hotspots' . The problem here is that by looking at a chart online, it is quite easy to simply dig to the 'hotspot y level' an start mining, and know you are going to quickly find the desired ore. What if these 'hotspot y levels' were generated randomly per world, within certain parameters? Then you would have to 'scout out' your world, and see where the best place to dig would be. Maybe certain areas off the world would have different hotspots. The player would then probably dig a large shaft, and try to find the layer with the most ore, and then dig there. Just a suggestion, but I reckon it could add a lot to the mining aspect of the game.