If you read the Dungeons and Dragons 'Manual of the Planes' this would probably make a lot more sense to you.

To save a bit of time, I'll stick on a screenshot or two since it also saves me from having to write something that is easy to pick up and read.
1) Dunno how it works out, nor do I know the intent of the author.
2) They’re earth. I’m sure they’re decent at shattering it.
3) I don’t know if the goal was to make it easy?
4) The wand of acid is actually called “a glass tube filled with corrosive acid”. That lets you know, up front, it is glass. It does an earth rift, just like the marble wand, I’m not sure whether the intent was to have it shoot acid or just do a rift. I’ll try to check on that.

5) Ice beats water. Ice melts to water, then water evaporates. Water JUST evaporates.

As far as I can tell on the CF mobs, both fire elementals and magma para-elementals are vuln to cold and drowning, with a bit more of a vulnerability to one over the other.





6) Fireballs -

Having it on top of water/surface -

7)

8) Some places are annoying, but have other trade-offs.
9) I’ve got no idea if this is consistent, but personally I’d be fine if they could all be dispelled. I’d also be fine if we want to say the ‘spell’ only kicked in to cause the shift, making a dispel after that point do nothing. Consistency is what would matter most to me here, but no idea how it currently fits.