Hmm. I recommend visiting this thread:
Jago is decidedly “enough” if you’re talking about capacity to compete at high level against the cast. It does take a certain mind and skillset, mind you, but Jago is very strong, even against some of the crazier characters in the cast.
As to the other point about characters’ balance being compromised to sell more of that character…we’ll have to agree to disagree. Gargos isn’t meant to be “normal” - he’s a boss and his overwhelming toolset is meant to reflect that. He also doesn’t seem very good at all at “noob” level; his offense is too layered and his defense is too bad for that to be the case. But reasonable people can disagree.