Winter Melon, Cob Cannon, Cattail and Gloom-Shroom are pretty obvious answers. I also love the Rockspike a lot. Other than that, nothing more useful than a properly placed Cherrybomb, Jalapeno, Squash or Doom Shroom.
By priority without add the sun plants, since it obvious. - Imitater. Use him to quickly make 2 col of sun plants. Then later, if you are in survival, change to another plant. - Mellow-pult with winter upgrade. Splash damage + slow = win. - Pumpkin. The best defender, since you can add another plant over him. - Magnet-shroom. Help a lot in defense and attack. - Spikeweed with Rock upgrade. The most resitant and strategic attacker.
All other plants have their advantages, but these one is to me the most important.
Have two Chompers on the front row. The most front one added with Pumpkin. Thus each row would have two reloadable mines. Pumpkin helps alot in protecting your Chompers. A Tall-Nut can work but that means you only can have one Chomper per row.
Zidane : You got the talent to be a bandit! How 'bout we team up? We'll call ourselves 'The Betrothed'. Dagger: My talent's up to snuff, but that name isn't.
I've decided to give fume shrooms a chance and I'm really liking them. Multiple rows of them is like a death sheet that hits every zombie that gets close, due to their penetrating attack. Of course the coffee bean needs to be used during the day, but I find the setup time even with that extra 75 cost during daylight is alot quicker than some of the better daylight plants, and more effective. Pumpkins and Rock Spikes of course compliment them well, and their upgrade in gloom shroom is wonderful for the front lines.