If you are facing gremlins or any crew with lots of cheap minions she is pure win! Think of all the wounds she will do, she will by pass hard to kill, hard to wound, she can summon minions who drop scheme markers when the die, so do that away from the enemy and you can place scheme markers up to 8" away.
She can give fast and reactivate so things like deliver message etc that are usually hard to achieve can be done alot easier.
I think you answered your own question to be fair though. You have listed everything she can do. Its just a case of thinking where this will be best applied. What's strat/schemes are on offer for the game?
Also I you need a master who is hard to take down she is the woman to turn to. Discard a cards to reduce damage down to one is so much better than using a stone. Use these stones with a really good henchman and your opponent is going to struggle.
Madame syb is a great choice being able to assist molly in moving around the table, saving mollys ap for other action points. Remember points make prizes