I believe Mijumaru should get the most screentime since Ash lacks a fully evolved water starter.Pokabu doesn't need any screentime because Last gen Ash's Infernape hogged all the spotlight and left his other Sinnoh pokemon with little development.As for the grass starter nope since after what happened to Torterra and how it lost every battle it was in lol,I doubt the writers will make the same mistake again.Charizard the fire starter,Sceptile the grass starter and Daikenki the water starter omg i can't contain my excitement x)