Lol Sickboy isn't about romance so Sun Goku and Goku will have no mercy XD
I'd probably be spoiling too much for potential readers bec the bigger stuff isn't apparent so
I hid it in spoiler below
In short yep the top tier are up in Goku's and Superman's league
and also anything with mammalian traits would instantly mutate into a feral monster if they were to come within a 20 ft radius of a Sick-Boy.
Spoiler
Ancient Gods are attached to it - left open to to reader interpretation and clues that may associate them with RL gods-
The mythos of the story: Gods created a frequency and upon listening to it, they attained their immense powers (pre-human existence)
Modern Man attempts to recreate said frequency and the plot ties back those gods as a result
Issandro [season 2] (can be interpreted as Mars/Aries)

He controls Gravity and Anti-Gravity
While he is still a deadly threat to the heroes from the start the 1st time around his powers are still rusty (because of his dormancy) so Goku would definitely have upper hand if he keeps distance. Overall he is a silent, observant, swift and constantly evolving ( think of him as Kratos from GOW meets Jason Vorhees meets Goku). He'd be able to create black holes, white holes, travel out of Erath's atmosphere and such.
Once he is back to himself he'd be on Goku's range or possibly be evolving further.
Also he's a skilled in capoeira (in his brainwashed state of dormancy as a human), Veto uses his Null Powers against Issandro, forcing them to fight each other hand-to hand. As a 'human' he won an International tournament called Impact Circle.
A few of the gods take the guise of pro-wrestlers on a popular TV program (think WWE)
Tyrannical Taurus (Gilgamesh inspired)

He has Reversal powers as well as superman strength and flight. His reversal powers allow him to flip the opponent's powers (super strong to super weak) and also allow him to embody the opposite of his opponent's power (becomes fire user if opponent is a ice user). He serves as Issandro's arch nemesis and a major antagonist. (season 2-3)
Mr. Patchez (can be interpreted as Hercules of sorts)

The bastard son of the King of Gods. The ancient gods trapped God of Death in order to grant their devotees immortality, throwing off the natural order, these gods became corrupt as a result.
He chose to restore balance and freed Death from his prison and was granted Death-pardon.
While he cant fly - he possesses herculean strength and death vulnerability. If you chop him up he will form right back. You might be able to drop him in an anti-gravity vault or somewhere to keep him sustained eternally.
(Superman Inspired)
Dr. Princeton (season 2/3)

Meant to be a horny version of Superman with the super-strength and flight capability etc.
Just one issue, he was recently infected with a form of vampirism and turns into a marble statue in sunlight (if you shatter the statue and scatter the pieces, he'll will still restore by morning and return to flesh by night). So fighting him is based on time of day and location. Guess you can leave him in the sun he'd just infinite loop as a statue melting and reforming until the sun stops shining and he's free once again.
Crimson Panda

- Superhuman style flight and strength, plus Superhuman Mimmicry.
His hot-blooded and reckless attitude can either be his downfall or lucky shot.
Veto-
Created by human tests and not a true god, he can Nullify the abilities of anyone who comes within range including all the aforementioned (except Taurus). He is a Taekwondo expert who placed 2nd to Issandro in the Impact Circle tournament and acts as a thorn on Issandro's side.
The puppetmaster (season 3)
Without giving too much he manages to puppeteer all these guys above from a distance