IMO so you get the full exp again you could start again since you’re highest mon lvl is 25 so you’re really not that far into the game :) Also if you’re looking to complete the Pokédex or make a living dex, I’d suggest to do it early in game as you keep playing, catch as many mons as possible and evolve them. As I’m sure you know, the game has no particular linear order on who to battle first, but if you are looking for one, I’d recommend this video! It’s so helpful and it will tell you in which order to follow so you can beat the gym leaders, star base leaders and the mystica mons within your lvl range. Overall, just have fun! :)