Your post was way too long bud, but I can tell you, after playing since soft release in Canada back in July, being a level 50 (+307 stars) with all the cards, I know I can kick any zombie's a$$ with my plant decks.
It's about knowing what cards your opponent could have in his hands. Each hero has a very limited amount of cards they could be playing. Like for example, when you know the game enough, you can anticipate which zombie is hiding under the tombstone they just played about 80% of the time. I know I do. I'm not saying this to brag at all, anyone can get to that point if they play enough.
My point is that this game is quite well balanced at the moment. Sure some minor tweaks could help here and there (on both sides), but overall, this is a very finely tuned game.