You didn't quite understand me. An individual's grapple should be similar to their strike value. So if someone like CM Punk has 65, then his grapple should not be lower than 53 at an extreme low.If you remember, grapple and strike used to be combined under strength in previous games.
But then again, someone like the Big Show can punch A LOT HARDER than CM Punk can. But he isn't a brawler, he is a powerhouse. I don't agree with the concept of Cena being able to punch somebody just as hard as Big Show could.
Stamina is a tricky area. I see your point on giving main-eventers more stamina. They tend to have longer matches, so it makes sense. But high-flyers like Rey Mysterio, Kofi Kingston and Tyson Kidd use a lot of running and high-energy moves, but do not tire easily. Their moves cause a lot of stamina drain, but they aren't really affected by this.
I agree with your points about Charisma. But perhaps they should be even lower.
Technique and submission are mainly defensive. Guys who can counter grapple moves are almost as capable of escaping submissions, sans finishers. So there should not be much of a gap. But for the most part, guys who normally win by submission tend to be good at countering grapple moves anyway.