Well of course PSZ is good. Gorz is, as I've said, not a necessity and could be shaved off, but still decent. Running Thunder King in only one copy though? That's inconsistent. Of course it's good once in a while because it's a good card, but a deck can run without it, often more efficiently than if it were still there. Mist Valley Soldier doesn't have much of a notable effect, and its only real utility is basically as a 4-star Tuner. It's an okay card, but it is very much replaceable and you can run better cards.
If you wanted to run Thunder King in plants (totally fine) you would run at least 2 or sometimes 3, not splash it as a singleton.