Discontinue use of QFE (and demand Russia does likewise).
Discontinue use of pressure altimeters (and thereby eliminate setting errors) except as backup to GPS altimeters.
Discontinue references to feet and metres in altimetry in favour of 'flight levels' throughout.
So an airliner cruising at FL330 has 33,000 indicated on its altimeters (as at present). A pilot flying circuits in his Cub or Cessna 152 will report his flight level (not altitude) as (for example) 14 (or 014).