I would say be careful of this if you only stick to a small team - they'll likely be overlevelled before long. I had a rotating team of 12+ all at the same level by the time I reached the end of the story and it gave me the SEMBLANCE of a challenge. That said, the max EXP share is super useful post game for levelling up Mons to finish the Pokedex and stuff. On that, I've gone back to Shield after putting it down post Elite Four (haven't finished the post game or got the legendary because I don't care and will do it later) to complete the Dex as much as I can. Done reasonable job and virtually down to just the Sword exclusives or Trade-evos I need now. Is the GTS a paid exclusive on Pokemon Home?