Bank robber Mysterio sounds like some lame campy Schumacher villain. How Mysterio supposed to be menacing if he spends 50 million dollars in special effects money to steal 100,000 dollars from a bank? It feels like writers have villains rob banks when they can't think of something more interesting for them to do,bank robbing is not the height of villainy.
Also if Mysterio is just some bank robber, how he unique from the likes of Shocker, Sandman, Electro, Rhino, Vulture, etc. What because his gimmick? Having half of Spidey villains be bank robbers makes them way less unique. We had campy Schumacher villains in the last Spidey movie, I want someone menacing this time.
Frankly I would make the campy personalty for Mysterio be a mask for a vicious and sadistic personality underneath, if all he has is the campy personality and nothing, he is going to come off as a campy Schumacher villain.
Also what are the stakes if Mysterio just robs banks the whole movie? What happens if Spider-Man fails to stop Mysterio from bank? Nothing really, the bank's insurance rate will go up and Mysterio will get away with some marked bills. Unless he is murdering the tellers and the customers, there is no reason to care, there should be no bank robberies in a Spidey film past Act 2, that should never be the climax of the film. Its on okay intro action scene for Spidey to stop a bank robbery, but you should move to bigger and better things from the villains as the film proceeds.
Mysterio trying to break Spidey's mind makes him unique and sets him apart from the other bank robbing villains out there, it makes for a truly unsympathetic villain, murderous mind breaker is more unsympathetic then a campy bank robber.