Imo, since I haven't been introduced to the games, I'm going off the movie. From experience, I know when there is a film adaptation of a game...they usually get it wrong if not horrible. I have yet to see a film adaptation of a video game that's actually holding true to the mythos of set game. Real quick: the new Mortal Kombat was good, but still lacked the game universe essence.
All writers and producers need to do is hold true to the genre they're trying to interpret through film. Again(Mortal Kombat), let's say if they created a movie behind the game stories of the MK franchise; the basics are already there...all you have to is follow the actual story of the games...(stay with game story content producers). Pretty sure they would have made more and have a better turn out amongst fans.
Now Monster Hunter, is a good movie by itself...beyond making Meagan Goods' character have falsies even though she is in an elite combat unit or why the dragon can be cut by a knife and damaged by an arrow with dynamite, but an Abrams tank sabot round can't kill it nor any of the other technicals firing upon it or it magically flying fast enough and higher than an Awacs jet...little things like that makes the direction a bit hard to believe...you'll point out the little inconsistencies throughout; I just pay a lot of attention to the small stuff that contradicts the real world. As mentioned, I never played the game, but I'm sure once I do...this movie will most likely be a subdued version of the game. For instance, Castlevania was a good adaptation of the game. But for the MH movie for what it is; its pretty good.