Tldr Amina is a bad version of Marie.
Taking a squared stat line of her (square all stats and add together, which imo is a more accurate estimation of min/max potential) she's a 36, whereas Marie is at a 43. Marie is hence the winner.
They both play a high risk game with doom on investigator assets. Amina reduces card cost, while Marie gets bonus actions for having any card with doom. Since you can take blood pact at level zero, Marie wins and her passive will see far more use.
Amina takes charms, which are rather useless. Mystics already have contested spots for charms, and this just adds off class options to her that ultimately don't improve her basic abilities... spells.
Marie can force stop doom from advancing the agenda at any point. If you mess up your doom manipulation, Marie can pardon this. Or you can go heavy doom in a witching hour, and then play her signature go give you another witching hour turn, risk free.
Amina's signatures just add doom to play all the time. Since she can't really cast meaningful spells with a 3 in charisma, it's not clear these assets do her any favors.
Baron Samedi is actually an asset for Marie in that he can proc her passive at any time. He can force the agenda to advance, but only if you mess the math up.
Deafening Silence on the other hand can make all the accumulated doom add up, immediately. It's like Cursed Memory, but worse.
Overall Rank: C.
Amina tries to fill a niche other mystics have already perfected. Although she can be effective, pretty much everything she can do can be done by Marie, better.