I turn off harder mining for your last reason. It's needless and arbitrary risk for no interesting gain. (I suppose stable warpstone is a benefit, but I've never made a warpstone lab, or seen much of a point to one.)
What really bothers me about is it is it's a completely regressive risk. All the danger is up front when you're at your weakest. Once you have a decent military and a guildhall it's almost zero risk. Until you have those things, death is random and sudden unless you micromanage a lot. And that needed micromanagement is at the beginning of a fort, when I'm already trying to hyper micromanage my initial 7 to get as much done as I can before anything bad hits me.
Now compare this to harder farming, smithing and smelting which are more progressive risks. Harder farming doesn't hurt you on day one when making your first burrow, but years later when you run out of food with 150 dwarves and/or have to defend above ground farms which can be harder to secure against late game flying invaders. Harder smelting only harms with any regularity once you have a robust metal industry. Harder smithing is only a pain if you're trying to make tons of armor or weapons out of metal, say to skill up to legendary for weapon/armor smiths.
Just my two cents