>>33246569Trainer levels can scale with your team (which I just realised is what BOTW monster camps do but with playtime).
Wild levels can scale as you get further from the starting point and in places behind HMable blocks. Another idea is a sort of sentry Pokémon that blocks the access to a higher level area.
If you walk near it, you can see its level. If you beat it, you get an area with Pokémon around that sort of level (probably a bit less).
Gym Leaders could scale with your number of badges, but then again if you spend ages in the wild you can overlevel. So maybe they should scale with your top 6 levelled Pokémon. Or maybe top x, where x is how many are in their team.
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The upside is using berries and herbs found in the wild that you can use to keep moving through the game, coming across a hidden area with rare Pokémon in it. You can catch Pokémon and use their HM-like abilities to traverse through the world, replacing existing fainted party members. Your team will have to stay fresh. Coming across evil team troubles in a non-scripted manner and dealing with them as you want. The sense of progression is more meaningful because you have to get past obstacles yourself (no pokeride handout); it's not that whenever you get stronger, all the Pokémon in the next area are stronger too.