With all of that being said, you could certainly build more heavily into Reshiram ex than this deck does, depending on what you are going for
Generally, our Signets, Myriad Landscape, and Servant of the Conduit can prevent us from falling behind while also helping to offset the hefty triple-green or triple-black mana costs for Aetherwind Basker or Demon of Dark Schemes
VSTAR Pokemon are less risky overall, and the difference in core power isn't necessarily equivalent to that extra Prize Card involved in knocking out VMAX Pokemon
While his stats are beefy, hes still a vanilla card with no effect, so hes not very popular among players, but he does still get some fringe play in certain Steel decks because, at the end of the day, big stats are big stats, and its nice to have a big dude to play if the game goes long
Avacyn eats removal consistently, so shes not quite as good as the card I want to name: Serras Emissary