Most of the banking-information-malware I take a look at hooks multiple browsers from the OS. So the browsers would need to be isolated in a better way than just being different browsers.

Using an uncommon browser for something like banking (Opera or Vivaldi or something) would be a pretty good solution because no one would have bothered to develop the hooks for them, unless the malware is keylogging, which is not uncommon but less popular now than the smarter solution of watching browser form submits on known bank websites.