Scotland vs England at Coventry would work best. A poor selling game in the north but smashing the Scots and lots of points make it a good sell to a newbie.
NZ vs Australia would be a good bet for London as the last game at the Stoop got some real interest going with the ex-pats. Unless they fancy trying the Olympic Stadium again, which was a great success last year.
England vs NZ/Australia will work anywhere in the north or London. Hull for the NZ game is a good bet as they have a poor record there. A win against NZ will get us into the final and that means £££ for the RFL. Maybe Wigan for the Australia game as that gives Lancashire a game.
The other two Scotland games are hard sells regardless of where they are. Maybe have these as double header openers?
Anfield sounds exciting but if you think there is no leg room at Old Trafford then you have never sat in the Centenary stand.