I think James is the protagonist with the strongest plan of following his father's orders to retrieve the smoking stand. Larry is the antagonist, who gets in the way of James's plan by delaying and obfuscating and following his own distractions. The resolution is the knowledge that not only is the smoking stand long gone, but the house and the childhood and the simple way of considering their family. It's not a happy resolution, nor is their journey complete, but I do think they change from beginning to end. Any ideas on how to deliver this more strongly?
There are lots of ways to proceed, but this is, in the end, YOUR story. So following your description, certain questions arise in my mind:
1. His father knows the house is burned down (though the viewer doesn't know that immediately). Why send these two brothers on this quest knowing that grandpa is on death's door?
2. Larry is not the 'classic' antagonist, IMO. He is the pivot of the story that teaches the life lesson. If I had to make a guess, the antagonist is the 'dying grandfather' whom we never see. The purpose of the film is to bring that out. Much as in Amadeus, we learn about Mozart by his impact on Salieri by flashbacks. Who is the grandfather that he can motivate this roadtrip for a possibly non-existent smoking stand?
3. What happened to to them that led to such different development--Larry backwards and childlike, James bitter and sophisticated? Unravelling that is the key to the family part of your story.
4. We know nothing of the family in this script. What I "saw" was a child-like Larry being put down by his younger brother James repeatedly without explanation. So a big responsibility, is to show me what this family was like. Just as important the missing characters--mother and grandmother. Where are they?
5. There are two storylines in every movie--the subjective (what the audience feels) and the objective (what the audience sees). You don't need to resolve the objective. But you MUST resolve the subjective or you leave the audience unfulfilled. So you need to identify what the emotions are that drive the passion, desire, and conflict for the character. Develop your arc and means they go from one end to the other ... typically. What drives James? Larry? (It's not about the smoking stand!)
6. What is the consequence of not returning with the smoking stand? Here, the father has set up the quest. Will this just be another of James' failures? In some ways, this is a "search for the holy grail", a quest to heal the Fisher King. In that sense, James is the questing knight and Larry his comedic, dimwitted page.
7. What is the significance of the smoking stand? Again, this is kind of a "holy grail" or "McGuffin" if you prefer. Whether they find it or not, its value is central to the character. It might be the ONLY way for James to prove himself to his father and grandfather so he sacrifices everything.
8. The burned down house is so strongly symbolic of the broken communications. That is worth exploring. What is this family about? The viewer is left to wonder if the grandfather accidentally burned down the house by knocking over the smoking stand. And by analogy, did he destroy the family by pitting brother against brother, father against son.
More than anything, these brothers need to come together. They need to see each other through a shared pain. I have my ideas about how to do this, but I really want this to remain your story.
What I love about it, even if it was totally unconscious as you wrote, is that the script is richly symbolic. James needs to go into himself, confront the source of that bitterness, and come out accepting. Larry starts as weak minded. However, he has survived and some of that insight can help James. James finds Larry is stronger than he believed.
For this script to work, EVERYTHING hinges on resolving their relationships, IMHO.
I may have deserved that. I think we're both in agreement what is needed to make it satisfying. My read is a "diamond in the rough". I see that rarely.
