**** all that. Bulbasaur all the way. Annihilates Brock and Misty. By the time you get to Surge you have a Geodude, Onix, or Sandshrew, and by the time you get to Erika you should have a Kadabra*, Growlithe, or Vulpix. Some of us don't have the time to level up a Charmeleon in the Viridian Forest.
*remember, every Grass pokemon in Gen.1 is also poison element except Tangela
Sure early on Bulbasaur makes dealing with everything up to Rock Tunnel a lot less annoying but you're giving up the best non legendary Fire type in the game (and is probably better than Moltres too) and Squirtle's Water Gun has far more uses on it over Bulbasaur's Vine Whip making it far more useful in Mt. Moon/Rock Tunnel.
Also Geodude, Onix, and Sandshrew are terrible against Lt.Serge himself as he likes to play like Guile and Sonic Boom everything in sight for fixed 20HP of damage. Which is inconveniently located at the one part of the game where fixed 20HP worth of damage is still potent (there's a good chance some of your guys are getting two shotted by Sonic Boom spam and higher defense pokes like Geodude and Onix tend to have less HP to make up for it).
Also also, Eggsecute and Eggscuator (or whatever the hell they're names are) are both Grass/Psychic. And also for Erika, why aren't you sporting Dugtrio? You can just grab one from Digletts' Cave and wreck everything forever with Dig, Slash, and eventually Earthquake.