The two most confusing things about "Field Mice" (Spoilers)

First, the probability or motivation behind Laozi helping Je Mun-jae to such an extent is too weak. Even if he is playing the role of a supporter in the plot development, it feels poorly written that he repeatedly passes up opportunities to risk his own life 4 or 5 times to help him.
Second, I also don't understand the motivation of the single killer hired by Park Seung-gyu to target Laozi/Je Mun-jae. Of course, it's likely money... and then suddenly, villagers from the countryside join in... (Wouldn't it have been better to just hit Park Seung-gyu and take all the money?) I keep wondering if there is a personal grudge against Je Mun-jae or Laozi.
Anyway, because it tries to contain too many stories, the pacing becomes long, and there were moments where I felt fatigued in the middle. As Laozi and Je Mun-jae began to resemble characters like Thelma & Louise halfway through, many elements felt disorganized. I feel a sense of regret that it might have been more dramatically tense if Laozi had been set up as a more ruthless character (obsessed with finding the money) and the "buddy movie" elements in the middle had been removed.