That's a great idea as well but likely, as you say, to be much more expensive especially in terms of travel costs.
This is where the 4N needs to be driven forwards to benefit the international game, not to line the pockets of the RFL, ARL or NZRL.
It certainly is not cheap, but with the right strategy I think it is possible to bring over Tonga and Samoa alongside Australia and NZ during a 4N year. We have now seen that there is a demand to watch these nations, although it should be recognised that these games would be outside of a WC.
France can get decent crowds, as can Wales in the right grounds, and I suspect Cumbria would flock to see the likes of Tonga and Warrington have an affinity with Samoa now.
We need to move away from the belief that these countries will only attract 1-2k, with the right plan and promotion they can absolutely be crowd favourites.