>>44306244So standard far route mons first leading through forest->field->Cave->Hidden Grotto/burial mound for ghosts->Mountain/cliffside->more generic field->Desert.
Second starter line cut for a new island/big advancement like how gen 6 split it's dex perhaps, so again some early route like mon with some stronger bst pokes thrown in->Safari Zone->Misc fields->Ocean->Icy region.
Third starter line cut is late game gift starter, all pokes after it are fossils, odd obtained gift mon,psuedo, and legendary