Yeah, (M) for resistance is inappropriate. Ice is weak to metal. You could put (M) as weakness, though.
Well, you could keep the weakness because think of it this way, look at Ninjask or Masquerain, they're (G) type and weak to (L). It doesn't make any sense (except in the Gameboy). They're bug flying type and in the card, they're bug type. In gameboys, Bugs aren't weak to lightning but flying does. So, instead of weak to (R), they'd put up (L) just for variety.
Confuse Ray is cool. Nothing to said here.
I thought Blizzard does something else. I think it's 'Flip a coin. If heads, does 10 to each of opponent's bench. If tail, does 10 to each of your bench.' (Sorry BT. Horrible grammar. But this is just, you know, template).
It said that on Articuno (Fossil).