For the people getting the game late, I just want to give some tips and facts about each vanilla classes in the game:
Plants
- Peashooter: The most deadly of all the plants in the right hands. It is also great for new people just getting into the game, because it is easy to master. It's only downside is having low health, which can be a problem against good players.
-Sunflower: Recommended for advanced players. It's low health and fragility make it an easy target. It also has a terrible attack. It is great for support though, remember to revive, revive and revive all the time. Once you master it, you can rack up a lot of "kill" points. Gardens and Graveyards is a great place to start using them.
-Chomper: Also recommended for advanced players, but for different reasons. This bad boy is SLOW and huge, which puts you at disadvantages, and makes you an easy target. But it has the highest health meter of all the plants, and can kill opponents with one hit by eating them. Is great to use them in Team Vanquish.
-Cactus: Great for new players, but has a higher learning curve than the peashooter. It is also not as versatile in the play style. It is a "sniper" class, which is not good in close combat, but makes it great for defending targets, and supporting teammates. It's onion drone makes it easy to pick opponents from far away. It is my favorite class on the plant side.
Zombies
Soldier- Same characteristic as the peashooter, but with a lower attack. It makes up for it by having a rocket luncher, and toxic grenades, which makes you think twice before going head to head with him. Great for new players.
Scientist- Advanced players only, as this zombies are extremely hard to master. It has the lowest health of the zombies, and it is only good at killing at close range. You do the math. The scientist is great for healing people, and it also has sticky grenades. If you are using it, please revive AND heal. Don't be that guy. Oh, and it also teleports. It is my favorite class on the zombie side.
Engineer- I love the shotgun power of this class, as it does splash damage! Recommended for veterans, because it is fat and slow. As the cactus, is the only other class that can fly drones. Great class for support.
All-Star- Deadliest of all the zombies and great for new players. It has a lot of health, which makes it feel like a tank. It is also fairly fast. It is great for kill assists and suppressing the opponent. It's only disadvantage is its size, which makes it stand out and be an easy target. Keep that in mind when using it, and you will be fine.
I hope that little guide helps. I'm not an expert on the game (rank 27), but by playing each class focusing on their strength, I've really enjoyed my first week with the game.