Yup, better than what they have, for sure.
My own "Came up with in 5 minutes, but is better" script was something like this:
Open with man running with two kids from iconic series monster, say a Deviljho or a Rathalos (if you wanna play it safe), he is downed by the beast, shouts his kids' names as screen blurs and the monster unleashes a torrent of flame in their direction. Opening credits.
Smash cut to protago-dad wearing war paint on a ship. Meet the other three hunters of the story and their pet comic-relief Palico, yadda yadda, establish that by coincidence they're all hinting the same monster, and that the trio are actually veteran hunters.
Same monster attacks the boat, hero does something horribly foolish in an attempt to get revenge, boat is shipwrecked as a result. The team then realizes, oh, he's a complete noob who is literally using a carving knife (or a regular blacksmith hammer) to fight and doesn't even have a proper weapon, and chew him out for his recklessness.
Party escorts the crew to a nearby village, they get attacked by pack of weaksauce monsters (Great Jaggi or Velocidrone), hero has to fight one on his own and gets saved by his posse when he nearly beats it but underestimates it and how monsters grow stronger when desperate. Hero realized how outmatched he is and that he should follow their lead. Time for act 2 to be about learning what it takes to be a real monter hunter who can work with a team and not some revengeful doofus with a knife.
They gear up in town, yadda yadda development, they fight another big monster to start solidifying their teamwork and the hero's new cooperation and maybe how his life skills can help them. Yadda yadda, they track the boss to it's lair, hero gets his own proper Monster Hunter weapon forged from one of the baddies they killed, etc.
They prep massive ambush of exploding barrels, drop traps, falling rocks, etc, track the monster and lead it into the ambush, cue the long and difficult final fight across an entire canyon, where the hero takes a hit trying to protect a critical backline ally, confirming he's grown and learned to cooperate. The party survives with some meaningful injuries, hero gets a big nasty scar, goodbyes happen, etc.
Hero returns to his previous life, having had his revenge, but he has his weapons and armor up on a wall. NPC person runs to him for shelter and tells him that his caravan was attacked by a rampaging Kut-Ku. Cut to hero charging out the door with his weapons and armor. Credits.
It gives the hero a meaningful but not overused motive, lets him be the proxy character for outsiders to the series, establishes a goal from the start, etc.
