Agree with all of the above -
@AngloScotsHybrid basing your opinion of whether a player can be effective in a position because of the way they 'look', is a very poor way to judge.
Jack Willis is only marginally shorter than Papali'i and I doubt anyone would complain if he'd been picked at 7 for England.
Savea has been one of the most effective carrying 8s in the world over the past few years - I can assure you, none of the players he's run over since he moved to 8 have thought he was 'too small'.