>>55458839I would just take things that already exist mechanically and make them into hard stats
>EnergyReplaces PP and now each Pokemon has a pool of energy to draw from for attacks, like Mana. It would not be based on a species but based on level, so all Pokémon at certain levels would have similar energy stats. You would still be able to use items like "PP Up" to increase it as well.
>GritThis replaces IVs. Now you can give a Pokemon Grit similar to Legends and it affects how much "extra" oomph any of their stats has. All Pokémon start at low grit, but through battling or using items they can increase all their stats at the same time across the board. It still has a max range like IVs so it basically is them for all intents, but now you have the ability to change it and visualize it as a flat across the board stat. This also means that Hyper Training now equals giving the Pokémon more grit and the different levels of bottle caps just give different amounts. Some wild Pokémon, especially later in the game, will have a higher grit stat naturally to reward you for catching them, but low level Pokémon will definitely have zero to low grit. This is also not tied to species but just level/experience, like EVs.
>FriendshipMake it a visible stat and separate it from whatever the hell that mechanic was introduced in Generation 6 with Pokemon Amie. Let it work like it used to: your Pokémon can either love or hate you based on different things you do and it affects things like evolution or the power of certain attacks. I would also make it affect whether they listen to you or not and to make it interesting tie it to the species as well. So certain species of Pokémon naturally have a lower friendliness and would be harder to "tame."
>Contest Stats These replace the Pokemon Amie mechanic that somehow got rolled into friendship. Now interacting with your mon in different ways affects the old five contest stats and those are the stats that let you evolve Sylveon, Milo