Every so often, there are suggestions to increase the boundaries of London to incorporate some of the adjoining suburbs and this is strongly resisted by those areas affecred. So here is an alternative suggestion - make London bigger by first making it smaller ....similar to Paris. The department of Paris is relatively small, but which is surrounded by three other departments which together constitute Greater Paris.
So why not create a series of Metropoltan Counties around outer London, for example Metro Essex which would include the recently (1965 ?) annexed parts of Essex - Havering, Barking and Dagenham, Redbridge, Waltham Forest etc - but which could then add adjoining areas of Essex - Brentwood, Thurrock, Epping Forest
Metro Kent could take Bromley, Bexleyheath and add Dartford, Gravesham, maybe Medway
Metro Surrey could take Croydon, Sutton, Kingston, Richmond and add Elmbridge, Epsom
Metro West Middlesex could include Spelthorne, and maybe Staines, South Bucks
Metro North Middlesex could incorporate Barnet, Borehamwood and Watford area (maybe different name for this area...?)
And together with the remaining central London, these would form Metropolitan London which would replace the GLA.
Some opportunities for fantasy maps....and excel spreadsheets...