Shinyhunting is really random in this game. Shinies are reasonably common on the last dungeons and poor chance of seeing one on early dungeons.
I think Shiny Pokémon should have a set Shiny percentage and adapt a little PMD touch to make everything balanced.
- Set percentage: 1/4096 (main game chance in Gen 6-present), 1/8192 (main game chance in Gen 2-5) or 1/16384 (this might be a little to much, but since the game have dungeons spawning a lot of 'mons, this can be crazy enough to be balanced).
- Shiny recruitment chance: Make a +25% boost, a 50% boost, a +75% boost or even a +100% boost! Y’know, recruiting in PMD is so hard and shinies are so rare that, you know, there’s like a 1/50000 chance of getting a Shiny! And what if the Shiny Pokémon is unrecruitable or something? I still remember my Shiny Sandshrew fail in my first run, in Pebble Cave, and how I’ll probably never meet it again…
- Shiny spawning techniques:
- Sweet Scent/Honey Chaining: For each Sweet Scent/Honey used in the same dungeon, there’s a +0,0010% boost of getting a Shiny. After spawning the first Shiny, the percentage boosts does not reset.
- Shiny Hatcher: If a Mystery Egg is hatched by a Shiny Pokémon, there’s a 5% chance of this Pokémon of being a Shiny instead of the usual, according to the set chance change suggestion, 1/4096/8192/16384.
- Cute Charm + Attract + Sweet Kiss = When a Pokémon with Cute Charm uses both Attract and Sweet Kiss on a Shiny Pokémon wit h opposite gender increases its recruitment rate by 5%. If the Cute Charm user is Shiny, then its recruitment rate increases by 10% instead.