I have had a chance to play with the character thanks to a friend, so I made an account just so I could add onto the "notes" for Marie.
For the weather super, you can just hold the button down for whatever weather you are trying to get. Her DP can be done in the air, and it also paralyzes people if her weather is set to cloudy. The 236236AB super actually has fast enough recovery that she can follow it up with 5BB in the corner. If done early in a combo, you can do a full combo after the 5BB. Otherwise, the person will be able to tech after the 5BB.
Yes, her 214CD is unblockable. It takes 25 meter to put out, and then 25 meter to activate. There is definitely a setup in the corner though with sweep > present oki. Trying not to blow 50% meter on a setup, so trying to make use of the fact that it blows up by itself after a while. Haven't completely figured that one out yet, but currently brainstorming it.