Uhhhhhh...
When you play Professor Brainstorm, slam down Binary Stars and next turn play a trickster for 12 Damage? Or nuke 2 of your on-board zombies for 1 brain each for Final Mission and deal 16 to their face... you can tell me how "overpowered" Plants are...
I think that the Balance between the two factions is just fine. I think the nail was hit on the head with:" it's really all about your deck, and your playstyle"...
I've lost tons of matches vs absolutely BRUTAL Plants Decks, as I have done the same with Zombies Decks...
I think that the Game Balance is actually VERY Good right now... possibly a few Very minor tweaks here and there on occasion as different small issues arise... Which seems to be what they have done, and have been doing.
Game is GREAT!