For once I agree with 411A and certainly with what rainbow says, until the punishment fits the crime the UK will be awash with crime because there is no proper deterrent and there never will be until some government realises there has to be proper law and order in the UK.
These women should be banned for life from flying, nothing less. Make them pay for the diversion plus costs, don't bother sending them to jail just ban them for life. No half measures or time off for good behaviour. No human rights issues here either.