I thinks Jeffles suggested format is a good one. I personally think the Tri series should be every second year. Alternating between the Northern and Southern Hemisphere, so the timing would revert to how it used to be we go to GB every 4 years and Gb to Australia every 4 years. I think that way the concept wouldn't be flogged to death as well as the burnout factor for the players. What fixtures could be scheduled in between is debateable, a 2 match series between 2 of the big three one year or a World sevens/nines tournament?