Well, Tron can give absurd amount of SP on Hardy stack only because people equip him with Green Skill Levels on SP mods. Otherwise it´d be pretty normal.
It´s also the reason why Mulan and others can do absurd damage with just one stack of hardy (like 7M white skill and such). With only +40 Levels, Tron´s SP give would be just about doubled.
Also, Tron deletes all buffs and that is OP right now (needs a limit, like Donald´s debuff absorption).
For Jack, Nick etc. the stats aren´t really bad per se, it´s just that the characters have not much else on them to begin with, their BD/SP share is considered the most valuable property. Hence why they don´t have absurd damage with crit on themselves (Mulan), quite an absurd amount of Reality/Armor/BD just by having the character in the team (Li Shang) or absurd damage combined with a debuff (Cheshire).
That´s all my talk around here. Double the stats on passive skills is fine. 7x isn´t no matter what way you put it. Besides, the bonus levels aren´t even shown on characters anyhow, which is concerning to say at least because… they are game breaking.
How can I know that THAT particular team with Tron will sweep me in 3 seconds, because Tron has +80 levels on Green Skill (just an example) ? I can´t see he has them. That´s not called a fair play since I am deficient on information that way.