Here is what I am comparing, Charizard, Blastoise, and Venusaur.

STAGES- they are all stage 2, so nobody gets a point

Charizard-0
Blastoise-0
Venusaur-0

HP- Charizard has 120, while Blastoise and Venusaur have 100

Charizard-1
Blastoise-0
Venusaur-0

STAGE 1- They are all about even. Ivysaur can poison, and his Vine Whip uses
lots of colorless. Charmeleon has lots of HP, and has an all colorless
attack. Wartortle has average HP and has a 40 damage attack which takes
almost all colorless energy. I give them all a point

Charizard-2
Blastoise-1
Venusaur-1

BASIC FORM- they all have pretty good attacks, but bulbasaurs ability to cure
himself gives him a point.

Charizard-2
Blastoise-1
Venusaur-2

POKEMON POWER- Blastoises pokemon power breaks the rules, Charizards works
great, because he can be used in any deck, and so can Charmeleon and
Charmander. Venusaur is good, but it's only usefull if you used him previosly
and have energy on him.Charizard and Blastoise get 2, and Venusaur 1.

Charizard-4
Blastoise-3
Venusaur-3

ATTACKS- Charizards mostly says "Discard 1 energy card for 50", Blastoises
Pokemon Power gives him lots of energy for 60, and Venusaurs is a pretty
normal attack

Charizard-5
Blastoise-5
Venusaur-4

WEAKNESS AND RESISTANCE- Blastoise gets the weakness point, because electric
is rarer than fire or water. Charizard is the only one with a resistance, so
he gets that point

Charizard-6
Blastoise-6
Venusaur-4

LAST, RETREAT COST- Charizard and Blastoise have 3C, so Venusaur gets the
point for only having 2C.

Charizard-6
Blastoise-6
Venusaur-5

Well, my conclusion is that Charizard and Blatoise are a little bit better
than Venusaur because of their Pokemon Powers and Weakness + Resistance.