Seriously 100% weakness to Magic? Who would ever use this standing stone? 100% magicka regeneration isn't even that useful...

seeing as how the only thing that kills me in this game is magic users I would avoid that stone at all costs.

It can be briefly useful to bump magicka regen while spamming spells to raise illusion, conjuration, alteration, etc.

Then for pitys sake replace it with something less suicidal.

Nope

Only when I'm transmuting iron to gold and can't be arsed to chop wood while the magicka bar fills.

Seriously? This game throws Magic Resistance at you. You can have much more than the cap. Sure, 100% is a lot, but 50% is manageable. Especially if you Absorb some of it anyway. I'm not saying it's efficient, but it's not like it's a deathsentence.