Jarome Luai has a major opportunity with Samoa, while Tonga is seen as holding an overlooked advantage over its opponents.
The tournament begins on Thursday night with Australia and New Zealand, the favourites, facing each other.
Australia coach Kevin Walters' team selections will be under scrutiny, including whether his decisions prove successful.
New Zealand also has an X-factor player who could make a significant impact, though the player is not identified here.
England's selection controversy is another issue to watch during the competition.
Several Papua New Guinea players could also attract the Chiefs' attention ahead of the club's inaugural NRL season.
For Walters, choosing Roosters premiership-winning pair James Tedesco and Sam Walker would have been the straightforward way to avoid the spotlight and possible criticism.