now as for some more stuff
cherry bomb is capable of one shotting 9-A characters, and then giga gargantuar can survive three of those cherry bombs, and giga gargantuars gets one shot by lawnmower, which then gets easily crushed by the attacks of zomboss, who also can TANK a ton of jalapeno attacks which are equivalent to cherry bomb
and then, if we're gonna go even further
so yeah, I think it's pretty clear at this point that pvz1 capping out at 9-A is a bit unrealistic
and as I mentioned before, cherry bomb already has damage values listed on it's profiles, and if we're using those then we can easily get characters like gargantuar, zomboss and cherry bomb itself to 8-C