I can't speak for mining as I don't have a miner that high in level, but I can say for sure that on my server, the mountains of Kun-Lai overflow with herbs that no one seems to want to go pick.
I'd wager a guess that those same mountains are probably full of mining nodes that no one goes after also. That doesn't fix your problem that the stacks sell for cheap, but you might be able to fill your bags faster there. *Shrug*
If anything, TC, try farming ore in one of the lower level areas as a vast majority of the time there are enemies around the node or somewhere near them. With the way enemies are grouped together so much in MoP, having to take time to clear out several mobs before being able to mine a node will start to get tiresome.
But if you do it in one of the lower level areas, they'll drop much faster or not aggro you at all.
There really doesn't seem to be a lack of nodes in any of the areas whether it's the starting area or Dead Wastes. You fill up your bags rather quickly without even realizing it regardless of where you're at.
On my DK who has Herbalism, I got 500 stacks of Green Tea Leaf (I know they're worth squat, but still) without even trying to farm them just from picking them up as I went along while questing and doing dailies. I also got plenty of Silkweed and Fool's Cap along the way, with the occasional Golden Lotus.
I've only got 2 stacks of Golden Lotus through all of my findings. They are rare as hell, just like Trillium.
Your = belonging to you, you're = you are, their = belonging to them, they're = they are, there = not here.