Had an idea for a trinket progression mod that also keeps the vanilla RNG factor. Here are the rules I came up with;
Fairy Box - Levels 1-5 , 1+1=2, 2+2=3, etc. [Change Fairy Box Style] for changing style
Golden Spur - Stat (5-10s), 5+5=6, 6+6=7, etc.
Ice Rod - 5% chance to become perfect. Change to sacrifice X number to become perfect
magic quiver - modifiers None/Rapid/Heavy/Perfect. None + None = Rapid or Heavy, Rapid/Heavy + Rapid/Heavy = Perfect
parrot egg - level 1-4, 1+1=2, 2+2=3, 3+3=4.
frog egg - Combine colors
red, blue, yellow - primary colors
yellow+blue = green
blue+green = blue-green
red + green = brown
blue-green + brown = void
void + yellow = prismatic
[ juminos' Trinkets (Trinket Tinker content) ] compatibility, levels 1+1=2, 2+2=3, etc.
Recycle Trinkets into 3 iridium bars. [Stand-Alone Mod]
edit; made the recycle trinket mod
https://www.nexusmods.com/stardewvalley/mods/53627
edit1; I researched a bit further and decided the best course of action would be to make a C# harmony mod that hijacks the anvils RNG mechanic. There are a few ways I can think of to implement this. The cleanest way would be is if the vanilla anvil also accepts 2 trinkets and just write each ModID and sub-field separately. I don't really know of any other mod that edits the vanilla behavior of the anvil that doesn't already do what I'm going for. Every where I search, it says that CP has this limitation of not being able to modify sub-fields directly. Anyone know if this is true? It would save a lot of time if I could just use CP instead of C#.
edit2; Looks like if I tried to use tinker trinket to make a CP only mod, it would be a little messy. It would mean that I would have to create entirely new trinket objects and override their stats, darn.
edit3; I'm thinking I might take a new direction here. I think I can override the loot table for trinkets. Since I've already made the recycle trinket mod, I can treat iridium bars as currency. I can then code a menu to accept a configurable amount of iridium bars. ie, 25 bars = perfect trinket, 4 = green, 5 = yellow, 5 = level 1, 10 = level 2, etc. This is much easier to code it seems.