Graham and Roby are both 32, they have a few more international years in them, however the 2021 World Cup will probably be a year or two too late for them.
I think this will be the last time we see SOL and Heighington in England shirts. Brown could be in contention next year, we haven’t got masses of quality half back waiting in the wings. Widdop could always revert to 6 if we bring in another full back, maybe Tomkins if he can find some form, I think Jack Walker will be there for 2021.
Watkins is the world’s best centre IMO, but we need a second. Percival, Gildart and Sutcliffe could be contenders there.
Good news this tournament will be shown on the BBC, that’s how you grow the England brand.