>>34075953The only major benefits were that it was an actual location in the region, and you paid for stuff with money rather than FC. You leveled up your plaza by trading online, the more you trade, the more NPC's would show up to upgrade your shit. Occasionally Gym Leaders would show up for extra fanservice and level up bonus too.
Basically just all-around more convenient and straightforward.
The facilities were also better, stuff to level up, EV train, and hatch pokemon, but Alola actually has the Palego which is even better, so nothing was really lost facility wise, it's just a bit more of a chore to use and progress the Plaza compared to Join Avenue
