>>38118231I don't care what anyone says, Pokemon was meant to be an open world game. Even more so than Zelda I would argue.
It doesn't have to be anywhere near the size of Breath of the Wild, but just enough room where you're able to explore.
Pokemon should be in the overworld with their own distinct personalities (Ex: a Gyarados might aggro you and start a battle while a Pichu will probably be timid and run from you), the gyms and wild Pokemon should scale up in level with the number of badges you have or your set difficulty, and you should be able to do gyms in any order (I would also like to see more gyms than needed to enter the league as well).